Sign up to receive free email alerts when patent applications with chosen keywords are publishedSIGN UP

Abstract:

Polymeric urethane dispersants with solubilizing polymer chains and with
reactive carbon to carbon double bonds are described. The reactive double
bonds facilitate molecular weight build-up of the dispersant on dispersed
particles (enhancing colloidal stability) or enhance the ability of the
dispersants to be crosslinked into a matrix material.

Claims:

1. A polyurethane dispersant comprising a polyurethane backbone and
attached solvent-solubilizing: a) polyether chains of
poly(C2-4-alkylene oxide), b) polyester chains, c) polyacrylic
chains, or d) polyolefin chains, or mixtures thereof; and optionally one
or more chain terminators wherein on average each dispersant molecule has
at least one reactive carbon to carbon double bond in either the
backbone, the solvent solubilizing chains, the chain terminators, or
combinations thereof.

3. The polyurethane dispersant of claim 1 wherein the each dispersant
molecule on average comprises at least one solvent-solubilizing
poly(C2-4-alkylene oxide) (polyether) chain.

4. The polyurethane dispersant of claim 3 wherein the
poly(C2-4-alkylene oxide) chain is the residue of a polyether which
contains two hydroxyl groups at one end of the polyether chain which
react with isocyanates and which hydroxyl groups are separated by not
less than 5 atoms.

5. The polyurethane dispersant of claim 1 wherein the polyester
solvent-solubilizing chain is the residue of a polyester which contains
two hydroxyl groups at one end of the polyester chain which react with
isocyanates and which hydroxyl groups are separated by from 5 to 17
atoms.

6. The polyurethane dispersant of claim 1 wherein the solvent-solubilizing
polyether chain contains the residue of a compound of formula 1whereinR
is C1-20-hydrocarbyl group;R1 is hydrogen, methyl or ethyl of
which less than 60% is hydrogen;R2 and R3 are each,
independently, C1-8-hydroxyalkyl;Z is C2-4-alkylene;X is --O--
or --NH--;Y is the residue of a polyisocyanate;m is from 5 to 150;p is
from 1 to 4; andq is 1 or 2.

7. The polyurethane dispersant according to claim 1 wherein the
solvent-solubilizing polyether chain contains the residue of a compound
of formula 2.whereinR is C1-20-hydrocarbyl group;R1 is
hydrogen, methyl or ethyl of which less than 60% is hydrogen;R4 is
an isocyanate reactive organic radical;R5 is hydrogen or an
isocyanate-reactive organic radical;Z is C2-4-alkylenem is from 5 to
150; andn is 0 to 1.

8. The polyurethane dispersant of claim 1 wherein the solvent-solubilizing
polyether chain contains the residue of a compound of formula 3.whereinR
is C1-20-hydrocarbyl group;R1 is hydrogen, methyl or ethyl of
which less than 60% is hydrogen;W is C2-6-alkylene; andm is from 5
to 150;

9. The polyurethane dispersant of claim 1 wherein the solvent-solubilizing
polyester side chain is the residue of a compound of formula
6R9O((O)C-A-O)mH 6whereinR9 is C1-50-hydrocarbyl
group;A is C1-26-alkylene and/or C2-26-alkenylene; andm is from
5 to 150.

10. The polyurethane dispersant according to claim 1 comprising a
polyurethane backbone and at least one attached solvent-solubilizing
polyester side chain.

11. (canceled)

12. The polyurethane dispersant as claimed in claim 10 wherein said
solvent solubilizing polyester side chain is obtainable or obtained from
a hydroxy carboxylic acid or lactone thereof containing from 1 to 26
carbon atoms, including mixtures thereof.

13. The polyurethane dispersant of claim 12 wherein said solvent
solubilizing polyester side chain is obtained from the lactone and said
lactone comprises ε-caprolactone or δ-valerolactone.

14. The polyurethane dispersant of claim 10 wherein the polyurethane
dispersant has polyurethane backbone and attached solvent-solubilizing
polyacrylate which further comprises from 10 to 180 milliequivalents of
an acid or amino group, including salts thereof for each 100 g
dispersant.

15. The polyurethane dispersant of claim 1 which further comprises from 10
to 180 milliequivalents of an acid or amino group, including salts
thereof for each 100 g dispersant.

16. The polyurethane dispersant of claim 1, wherein said dispersant has a
polyurethane backbone portion that is essentially linear as opposed to
the polyurethane backbone portion being highly branched or essentially
non-linear and said solvent-solubilizing chains are laterally attached.

17. The polyurethane dispersant of claim 1, wherein said dispersant has a
polyurethane backbone portion that is essentially non-linear meaning that
the polyurethane backbone contains branches either derived from
isocyanate reactants that have more than two isocyanate groups and/or
reactants with Zerewitinoff active hydrogen groups that have higher
functionality than two when reacted with isocyanates.

18. The polyurethane dispersant of claim 1, wherein said dispersant is
obtained or obtainable by first reacting an isocyanate having a
functionality of at least two with a hydroxy functional
solvent-solubilizing chain to form an isocyanate functional solubilizing
polymer, thereafter reacting said isocyanate functional solubilizing
polymer with a reactant to couple a portion of said isocyanate functional
solubilizing polymer, optionally reacting the additional reactants which
are reactive with said isocyanate groups, wherein the reaction of said
isocyanate with hydroxyl functional solvent-solubilizing chain, reactant
to couple, and optional additional reactants such as chain terminators
forms a polyurethane backbone having at least one solubilizing chain,
wherein on average each polyurethane backbone having at least one
solubilizing chain has on average at least one reactive carbon to carbon
double bond in either the polyurethane backbone, the at least one
solubilizing chain, the chain terminator, or combinations thereof.

19. The polyurethane dispersant of claim 1 wherein the number-average
molecular weight of the polyester, polyether, polyacrylate or polyolefin
solvent-solubilizing chain is from 300 to 10,000.

20. (canceled)

21. The polyurethane dispersant as claimed in claim 1 wherein the total
weight percentage of solvent-solubilizing chains is not less than 5%
based on the total weight of the dispersant

22. A composition comprising a particulate solid, a vehicle in which the
particulate solid is dispersed and a polyurethane dispersant comprising a
polyurethane backbone and attached solvent-solubilizing: a) polyether
chains of poly(C2-4-alkylene oxide) b) polyester chains, c)
polyacrylic chains, or d) polyolefin chains or mixtures thereof; and
optionally one or more chain terminators wherein on average each
dispersant molecule has at least one reactive carbon to carbon double
bond in either the backbone, the solvent solubilizing chains, the chain
terminators, or combinations thereof.

23. The composition according to claim 22, wherein said polyurethane
dispersant has been adsorbed onto said particulate solid and partially or
fully chain extended or crosslinked through chemical reactions of said
reactive carbon to carbon double bond of said dispersant.

24. The composition of claim 23 further comprising a free radically
polymerizable monomer.

25. (canceled)

26. (canceled)

27. (canceled)

28. The composition according to claim 22, in the form of a millbase,
paint ink, or molding compound.

29. The composition according to claim 22, wherein said polyurethane
dispersant is at least partially adsorbed on the surface of said
particulate solid and after adsorption becomes chemical crosslinked or
chain extended via reaction(s) of said at least one reactive carbon to
carbon double bond with either a di or polyamine compound or via free
radical reactions.

30. (canceled)

31. (canceled)

32. (canceled)

33. (canceled)

34. (canceled)

35. A polyurethane dispersant according to claim 1 comprising a urethane
backbone and laterally attached side chains, further comprising a
nitrogen in a non-reactive amine (non-reactive with respect to
isocyanates) laterally attached to the polyurethane backbone such that
said nitrogen atom is separated by at least two atoms from the closest
atom on the backbone.

36. (canceled)

Description:

FIELD OF INVENTION

[0001]The invention relates to the polyurethane dispersants with carbon to
carbon double bonds themselves and to their use for dispersing particles
(e.g., pigments) in liquid media. In the first embodiment, once the
dispersion of particles has been made, the dispersants may be crosslinked
with a suitable crosslinking agent (e.g., polyamine or via free radicals)
to lock them onto the particle surface. Alternatively, the dispersions
may be utilized in coatings, inks or other formulations where the binder
material contains reactive unsaturation which is cured after the addition
of the dispersion. The polyurethanes may have linear or non-linear
backbones.

BACKGROUND OF THE INVENTION

[0002]U.S. Pat. No. 3,393,162 to ICI titled Block and Graft Copolymer
Dispersants claims a process for coating solid particles with organic
polymeric material including the steps of dispersing said particles in a
liquid containing block and/or graft copolymers, said copolymers
comprising polymeric components of different degrees of polarity, varying
the polarity of the liquid to precipitate at least one but not all of
said polymeric components on said particles, whereas said block and/or
graft copolymers thereafter function as a dispersion stabilizer for the
particles.

[0003]U.S. Pat. No. 6,262,152 to E. I. du Pont discloses dispersions
containing a liquid vehicle (which can be aqueous, semi-aqueous), organic
or inorganic particles (or mixtures) that are insoluble in the liquid
vehicle and a polymeric dispersant, having improved stability when the
insoluble segment(s) contains cross-linking groups which are cross-linked
to itself or a cross-linking compound to form an encapsulated network
that entraps the particles, which are particularly useful for paints or
inks in coating and printing applications.

SUMMARY OF THE INVENTION

[0004]Polyurethane dispersants with on average at least one reactive
carbon to carbon double bond per molecule can be made. They are useful in
making dispersants that either a) form more stable dispersions due to
chain extension/crosslinking reactions (by Michael addition reaction with
a polyamine or by free radical mechanisms) of the dispersants after said
dispersants have adsorbed themselves on a particle surface or b) can be
free radically crosslinked into various binders or continuous phases if
such binders/continuous phases are reactive with carbon to carbon double
bonds.

DETAILED DESCRIPTION OF THE INVENTION

[0005]Dispersants containing reactive carbon to carbon double bonds serve
to solve problems in 2 areas. Dispersants with reactive carbon to carbon
double bonds can co-cure with unsaturated binder systems e.g., sheet or
bulk molding compounds or radiation cure systems (UV or electron beam).
Use of a conventional dispersant in coatings, inks or resin systems
(e.g., sheet molding compounds) which cure through polymerization after
application can lead to a reduction in performance of the coating or
article. As normally the dispersant is a non-reactive component in the
curing system, it may (i) serve to extend cure time, (ii) lead to
softening or plasticisation of the final film (iii) potentially be exuded
from the final film which may manifest itself as blooming. The presence
of reactive double bonds within the dispersant of this disclosure enables
the dispersant to be incorporated and bonded into the cured matrix during
polymerization thereby reducing or eliminating the negative effects of
the conventional dispersant.

[0006]The stability of pigment dispersions with conventional dispersants
can be adversely affected by changes in conditions e.g., when the pigment
dispersion is letdown into the coating composition or if it experiences
elevated temperatures or a change to a different solvent mixture.
Introduction of other pigments or particulate matter may also cause
preferential adsorption of the dispersant by a second pigment source
leading to destabilization of the original pigment dispersion due to
dispersant depletion from the initial pigment.

[0007]Conventional dispersants adsorb onto pigment surface and an
equilibrium is established with free dispersant in continuous phase. For
a pigment dispersant to remain effective in providing a steric and/or
electrostatic barrier to flocculation the conventional dispersant must
remain substantially adsorbed to the pigment. The equilibrium position
can be affected by change in temperature, change in solvent, etc. The
strength of the adsorption (i.e., equilibrium position between free and
adsorbed dispersant) will also vary depending on the nature of the
pigment.

[0008]Although not wishing to be bound to any specific mode of action, the
following schematic illustration is included to help explain the problem.

[0009]If the dispersant can be crosslinked or chain extended to a higher
molecular weight after adsorption to the pigment surface, it will then be
locked in place or become less soluble in the continuous phase and
therefore much less able to desorb. Therefore, the stability of the
pigment dispersion is much less prone to be adversely affected by the
changes in environment (vehicle composition, temperature, etc.) as
discussed above.

[0010]Polyurethane based dispersants enable ready incorporation of
reactive double bonds in a simple single stage, single pot reaction. The
reactive double bonds can either co-cure with a reactive binder system or
react with external crosslinkers such as polyamines to form an
encapsulated network thereby offering flexibility in dispersant design
and application area.

EMBODIMENT 1

[0011]One embodiment of this invention involves modification of
dispersants having laterally attached solubilizing side chains and
essentially linear polyurethane backbones to contain one or more carbon
to carbon double bonds. These are shown in the following schematic
representations where circles represent repeating units from monomer and
the wiggly lines represent either lateral solubilizing side polymer
chains or terminal solubilizing chains. X' represents optional acid or
amino groups ("c") described later. The first figure represents a
polyurethane dispersant without any carbon to carbon double bonds.

[0012]Residue of lateral solubilising polymer chain with two isocyanate
reactive groups at one end of the chain (component b)

[0012][0013]Residue of monofunctional chain terminator which is
polymeric in nature (component e)

[0014]The reactive double bond can be incorporated in several ways either
at a) end of solubilizing chain or b) from monomeric species or
combinations. Three possibilities from a plethora of possible structures
are shown below.

[0015]Residue of monofunctional chain terminator which is polymeric in
nature and contains a carbon to carbon double bond (component e)

[0015][0016]Residue of monofunctional chain terminator which is
monomeric in nature and contains a carbon to carbon double bond
(component e)

[0016][0017]Residue of lateral solubilising polymer chain with two
isocyanate reactive groups at one end of the chain and contains a carbon
to carbon double bond at the other end (component b)

[0018]Embodiments 1, 2, and 3 are similar in that all have a polyurethane
backbone and solvent solubilizing chains. Embodiment 1 differs from
embodiments 2 and 3 in that most of the urethane forming monomers are
monofunctional or difunctional (rather than tri or higher
functionalities) such that the polymer backbone (defined as the molecules
directly between the reactive groups of each difunctional monomer) is a
linear backbone. The laterally attached side chains (solubilizing chains)
in this embodiment are chemically bound as a side chain to the initial
monomer and thus are lateral side chains to the polyurethane backbone
when it is formed. The polyurethane dispersants of embodiment 1 may be
prepared by any polyurethane synthesis method known to the art and are
readily obtainable or obtained by reacting together:

[0019]a) one or more polyisocyanates having an average functionality of
from 2.0 to 2.5;

[0020]b) one or more compounds (solvent-solubilizing) having at least one
polyester, polyether, polyacrylate or polyolefin chain and at least two
groups which react with isocyanates which are located at one end of the
compound such that the polyester, polyether or polyacrylate chain(s) is
laterally disposed in relation to the polyurethane polymer backbone; A
portion of these chains, up to 100%, may contain one or more carbon to
carbon double bonds.

[0021]c) optionally, one or more compounds having an acid or amino group,
including salts thereof, and at least two groups which react with
isocyanates;

[0022]d) optionally, one or more formative compounds having a number
average molecular weight of from 32 to 3,000 which have at least two
groups which react with isocyanates; A portion of these compounds, up to
100%, may contain one or more carbon to carbon double bonds.

[0023]e) optionally, one or more compounds which act as polyurethane chain
terminators which contain one group which reacts with isocyanates; A
portion of these compounds, up to 100%, may contain one or more carbon to
carbon double bonds.

[0024]f) optionally, one or more compounds which act as chain terminators
which contain a single isocyanate group. A portion of these compounds, up
to 100%, may contain one or more carbon to carbon double bonds.

[0025]As noted hereinbefore, the polyurethane dispersants of embodiment 1
have an essentially linear backbone and consequently it is much preferred
that components (b), (c) and (d) contain only two groups which react with
isocyanates. It is also preferred that component (a) has a functionality
of from 2.1 to 2.0 and especially about 2 since this also limits any
cross-linking/branching between chains of the polyurethane dispersants.

[0026]Double bonds can be present in any or all of the components (b),
(d), (e) or (f). It is essential for the invention that double bonds are
present in at least one of these components.

[0027]It is preferred that the average functionality of carbon to carbon
double bonds in the dispersant molecule is at least one. It is especially
preferred that the average functionality of double bonds in the
dispersant molecule is at least about two.

[0028]It is preferred in some embodiments that component (f) is absent.

[0029]It is preferred that double bond(s) are present in (b) and/or (d)
and/or (e). It is especially preferred that the double bonds are present
in component (e).

[0030]It is preferred that the double bond or bonds in component (b), if
present, are located at the opposite end of the chain to the isocyanate
reactive groups.

[0031]It is preferred that the double bonds present in the dispersant are
reactive in polymerization with other unsaturated components used in
reactive coatings such as radiation curable coatings and inks or sheet
molding compounds. The double bonds present in the dispersant should
therefore copolymerize with monofunctional and polyfunctional
(meth)acrylate monomers and oligomers and styrenic monomers.

[0032]It is preferred that the double bonds present in the dispersant are
activated towards the addition of primary and secondary amines.

[0033]It is preferred that the double bonds present in the dispersant are
present in methacrylate or acrylate ester functionalities. It is
especially preferred that they are present in acrylate esters.

[0034]Examples of materials for component (e) that contain one or more
double bonds are of two types.

[0040]where R═H or alkyl. R is preferably H or methyl. R is especially
preferred to be H.

[0041]Several grades are commercially available e.g., from Cognis.

[0042]n+m=2 to 100, preferred 3 to 50, especially 5 to 50

[0043]ii) Monohydroxy polyester (meth)acrylates.

[0044]A specific example for illustrative purposes of a monohydroxy
polyester (meth)acrylate is obtained from polymerization of
ε-caprolactone in the presence of hydroxyethyl acrylate.

[0045]Examples of materials for component (d) that contain one or more
double bonds are glycerol acrylate and glycerol methacrylate.

[0046]One method used for generating materials of component b which
contain a double bond is to react a monohydroxy polymer chain containing
a carbon to carbon double bond onto a diisocyanate with differential
reactivity of the two isocyanates groups (such as 2,4-TDI) and then react
that adduct with a dialkanolamine such as diethanolamine to generate the
dihydroxy adduct. The reactivity of the carbon to carbon double bond
towards Michael addition of the amine is desirably such as to compete
significantly with the addition of the amine to the isocyanate residue.
An illustrative example shows the reaction for a (meth)acrylate ended
monohydroxy polylactone chain. The desired product together with the
potential undesired product are illustrated. The desired reaction will be
more favoured for methacrylate functional chains (with R=Me) in the
following scheme.

[0047]Another way a (meth)acrylate functionality could be introduced is to
use a modification of the method described in EP43966.

[0048]In EP43966 compounds of the general formulae

[0049]are disclosed.

[0050]From a translation of the original German patent R3 is
described as follows

[0051]R3 is a protective group optionally removable again by
cleavage. This is introduced before the acetal or ketal cleavage, by
reacting the hydroxyl group with a compound which is monofunctional and
has a group reactive towards the hydroxyl group. Here, the reaction can
take place by substitution or addition. An example of a substitution
reaction is the reaction of the hydroxyl group with an alkyl halide,
e.g., methyl chloride, or an alkyl aryl halide, e.g., benzyl chloride,
wherein the hydrocarbon residue can have 1 to 12 carbon atoms. An example
of a suitable addition reaction is the reaction of the hydroxyl group of
the polyether with an organic monoisocyanate, e.g., an alkyl or aryl
monoisocyanate, or a vinyl compound, e.g., acrylonitrile, methyl acrylate
or methyl vinyl ketone.

[0052]The blocking of the free hydroxyl group on the opposite polyether
chain end to the starting alcohol can however be effected under
conditions such that, if desired, the protective group can be cleaved off
again. Thus, for example, it is possible to esterify the hydroxyl group
with an organic monocarboxylic acid or an acid chloride. Corresponding
esterifications are also possible with other acids, e.g., sulphonic acid.
After the cleavage of the ketal or acetal group and after the
polymerization of the 1,2 or 1,3-diol formed, the end-blocking ester
group can be removed by saponification.

[0053]A preparation is therefore illustrated by the following scheme

[0054]If the blocking of the hydroxy group were carried out with
(meth)acryloyl chloride or an isocyanoto(meth)acrylate, then a
(meth)acrylate ended material would be realized.

[0055]Methacryloyl chloride may also be used in place of acryloyl chloride
to generate a methacrylate functionality.

[0056]The preparation of the polyurethane polymer/prepolymer may be
carried out in the presence of a catalyst. Particularly preferred
catalysts are tin complexes of aliphatic acids such as dibutyl tin
dilaurate (DBTDL) and tertiary amines.

[0057]The preparation of the polyurethane polymer/prepolymer is carried
optionally in the presence of a polymerization inhibitor such as
hydroquinone or butylated hydroxy toluene.

[0058]The preparation of the polyurethane polymer/prepolymer may be
carried out in an inert atmosphere, which may be provided by any of the
inert gases of the Periodic Table, but is preferably nitrogen. The
preparation of the polyurethane polymer/prepolymer may also be carried
out under an atmosphere of air to assist inhibition of the polymerization
of reactive carbon to carbon double bonds present. When the presence of
oxygen is desired to assist inhibition of the polymerization of reactive
carbon to carbon double bonds present, but flammability of the
polymerizing mixture is a concern the preparation may be carried out
under an atmosphere of depleted oxygen which typically contains 1-10%
oxygen.

[0059]The essential feature of the polyurethane polymer according to
embodiment 1 is that it comprises a predominantly linear polyurethane
polymer backbone containing defined amounts of lateral polymeric side
chains (solvent solubilizing) which may be poly(alkylene oxide),
polyester, poly(alk)acrylate or polyolefin. There will thus be many
variants which will be obvious to the skilled addressee regarding the
ratio of isocyanate groups to isocyanate reactive groups including the
formulation of prepolymers which have residual isocyanate functionality.
In one case, the ratio of total isocyanate groups provided by component
(a) is less than the total number of isocyanate reactive groups provided
by component (b) and components (c) (d) and (e) when present. Any
terminal isocyanate reactive groups may be reacted.

[0060]Whereas, the polyester, polyether, polyacrylate or polyolefin chains
may contain a terminating hydroxy group remote from the polyurethane
backbone it is much preferred that such chains carry a [terminating]
group which is not reactive with isocyanates since this restricts any
cross-linking during the preparation of the dispersant. The terminating
group remote from the polyurethane backbone may contain a carbon to
carbon double bond otherwise it is preferred that it is a
C1-50-hydrocarbyl group. The hydrocarbyl group may be optionally
branched alkyl, cycloalkyl, aryl or aralkyl. In some aspects, it is
desirable that the hydrocarbyl group contain one or more carbon to carbon
double bonds. The cycloalkyl group is preferably C3-6-cycloalkyl
such as cyclopropyl and especially cyclohexyl. The aryl group is
preferably C6-10-aryl such as naphthyl and especially phenyl which
may be substituted by halogen, C1-20-alkyl or C1-20-alkoxy. The
aralkyl group is preferably 2-phenylethyl and especially benzyl where the
phenyl ring is optionally substituted by halogen, C1-20-alkyl or
C1-20-alkoxy. The hydrocarbyl group here and elsewhere in this
disclosure is desirably substantially hydrocarbon but in some aspects up
to 1, 2, or 3 oxygen, nitrogen, or sulfur atoms may be present for every
10 carbon atoms.

[0061]The length of the alkyl terminating group of the polyester,
polyether, polyacrylate, or polyolefin chain depends to a large extent on
the nature of the organic medium. Thus, for example, when the vehicle is
a polar organic liquid, the hydrocarbyl group is preferably
C1-12-alkyl which may be linear or branched. The hydrocarbyl group
includes ethyl, propyl, isopropyl or mixtures thereof. When the
polyurethane dispersant contains polyether side chains it is preferred
that the terminating alkyl group is C1-4 alkyl, for instance methyl,
because of their ready commercial availability. When the vehicle is a
non-polar organic liquid it is preferred that the terminating alkyl group
contains greater than 8 carbon atoms. It is also preferred that the alkyl
group is branched since this aids solubility in the non-polar organic
liquid.

[0062]The alkylene moiety of the (C2-4-alkylene oxide) group may be
linear or preferably branched and may be obtained by (co)polymerization
of alkylene oxides such as ethylene oxide, propylene oxide and butylene
oxide or from tetrahydrofuran. Copolymers may be random or block
copolymers.

[0063]The polyester chain is preferably obtainable or obtained from a
hydroxy carboxylic acid containing from 1 to 26 carbon atoms or a lactone
thereof. The choice of hydroxy carboxylic acid is largely influenced by
the nature of the organic medium itself. Where the vehicle is a polar
organic liquid, the hydroxy carboxylic acid preferably contains up to 8
carbon atoms and where the vehicle is a non-polar organic liquid the
hydroxy carboxylic acid preferably contains more than 8 carbon atoms. It
is particularly preferred that the polyester chain is obtainable from two
or more different hydroxy carboxylic acids or lactones thereof since this
aids solubility in the organic medium. The hydroxy carboxylic acid may be
saturated or unsaturated, linear or branched.

[0067]By way of an obvious variant, the polyester, polyether,
polyacrylate, and polyolefin solvent solubilizing chains may themselves
be mixtures of such chains. Thus, for example, the polyester and
polyacrylate side chains may contain a polyether moiety and so on.

[0068]The number-average molecular weight of the solvent-solubilizing
polyester, polyether, polyacrylate, or polyolefin chains in the
polyurethane dispersant is preferably not greater than 10,000, more
preferably not greater than 4,000 and especially not greater than 2,500.
It is also preferred that the number-average molecular weight of the
lateral polyester, polyether and polyacrylate chains is not less than
300, more preferably not less than 600 and especially not less than 800.

[0069]The lateral side chain polyester, polyether, polyacrylate or
polyolefin chains in embodiment 1 are connected to polyurethane backbone
by oxygen and/or nitrogen atoms which are the residue of terminating
hydroxy and amino (primary and secondary) groups of the polyester,
polyether, polyacrylic (especially polyacrylate) or polyolefin.

[0070]When the lateral side chain is a polyether of embodiment 1, it is
preferably the residue of a polyether which contains either two hydroxyl
groups or one hydroxyl and one secondary amino group (both predominantly
at one end of the lateral side chain) which react with isocyanates. The
hydroxyl and/or amino groups are preferably separated from each other by
up to 6 carbon atoms. In one embodiment, when the polyether contains two
hydroxyl groups which react with isocyanates, they are preferably
separated by up to 17 atoms, especially 16 carbon atoms and one nitrogen
atom. It is also preferred that the two hydroxyl groups are separated by
not less than 5 atoms, especially 4 carbon atoms and one nitrogen atom.
It is also possible to prepare the dispersant from a polyether which
contains two amino groups (i.e., primary and/or secondary amino groups)
which react with isocyanates but this is less preferred.

[0071]When the lateral side chain of embodiment 1 is a polyester, it is
preferably the residue of the polyester which contains two hydroxyl
groups at one end of the polyester chain which react with isocyanates.
The hydroxyl groups are also preferably separated by up to 17 atoms,
especially 16 carbon atoms and one nitrogen atom. It is especially
preferred that the two hydroxyl groups are separated by not less than 5
atoms.

[0072]When the lateral side chain is a polyacrylate of embodiment 1, it is
preferably the residue of a polyacrylate which contains two hydroxy
groups at one end of the polyacrylate chain which react with isocyanates.
The two hydroxyl groups are preferably separated by up to 4 carbon atoms,
for example, 2 carbon atoms. In one embodiment, the polyacrylate is
present and in another embodiment the polyacrylate is absent.

[0073]When the lateral side chain of embodiment 1 is a polyolefin, it is
preferably the residue of a polyolefin which contains either two hydroxyl
groups or one hydroxyl and one secondary amino group which react with
isocyanates at one end of the polyolefin chain. The hydroxyl and amino
groups are preferably separated by up to 6 carbon atoms. When the
polyolefin contains two hydroxyl groups which react with isocyanates,
they are preferably separated by up to 17 atoms, especially 16 carbon
atoms and one nitrogen atom. It is also preferred that the two hydroxyl
groups are separated by not less than 5 atoms, especially 4 carbon atoms
and one nitrogen atom. It is also possible to prepare the dispersant from
a polyolefin which contains two amino groups (i.e., primary and/or
secondary amino groups) which react with isocyanates but this is less
preferred.

[0074]The dispersant may also optionally contain an acid and/or amino
group, including salts thereof, since such groups have been found to
improve the dispersability of some particulate solids. The amount of acid
and/or amino groups in the polyurethane dispersant is preferably from 10
to 180, more preferably from 20 to 110, and especially from 20 to 60
milliequivalents for each 100 g polyurethane dispersant. It is preferred
that the dispersant contains acid and/or amino groups. For acid, it is
preferred that these are carboxylic acid. For amino groups, it is
preferred that these are tertiary or aromatic.

[0075]When the acid group is in the form of a salt, it may be the salt of
an alkali metal such as sodium, potassium or lithium, a salt of an amine
such as C1-8-alkylamine or C1-8-alkanolamine or a salt of a
quaternary ammonium cation such as a C1-8-alkyl quaternary ammonium
cation or benzalkonium cation. The amino group may be quaternised. This
may be achieved, for example, by reaction with a dialkyl sulphate, such
as dimethyl sulphate or benzyl chloride. Preferably, the acid group, when
present, is in the form of the free acid.

[0076]When the amino group is in the form of a salt, it may be the salt of
an inorganic or organic acid. Examples of such acids are inorganic acids
such as hydrochloric acid and organic acids such as those containing
carboxylic acid group(s) (e.g., acetic acid), sulphonic acid group(s) or
phosphonic acid groups. Preferably, the amino group, when present, is in
a non-ionized form.

[0077]The polyurethane dispersant may in addition to lateral side chains
also have terminal solvent solubilizing polyester, polyether,
polyacrylate or polyolefin chains. Such chains are similar to those
described hereinbefore for the lateral chains but are obtainable from
compounds having only the one group which reacts with isocyanates. The
solvent-solubilizing chains with one reactive group are used extensively
in embodiments 2 and 3.

[0078]The total weight percentage of the solvent-soluble lateral and
terminal chains in the polyurethane dispersant is preferably not less
than 20%, more preferably not less than 30% and especially not less than
40%. The solvent soluble lateral and terminal chains are similar in that
both types are primarily chemically bonded to the polymer backbone at one
end of the chains and thus the non-bonded end of the chain has
significant mobility to extend into the solvent phase. It is also
preferred that the total weight percentage of solvent-soluble lateral and
terminal chains in the polyurethane dispersant is not greater than 90%,
more preferably not greater than 80%, for instance 45% to 80% or 60% to
78%. In one embodiment, the total weight percentage of solvent-soluble
lateral and terminal chains in the polyurethane dispersant is not greater
than 70%, for instance 55% to 65%.

[0079]The weight percentage of solvent-soluble lateral chains in the
polyurethane dispersant is preferably not less than 5%, more preferably
not less than 15% and especially not less than 25% or not less than 35%.

General Uses of Dispersant

[0080]According to the invention, there is provided a non-aqueous
composition comprising a particulate solid, an organic medium and a
polyurethane dispersant having an essentially linear backbone with
laterally attached solvent-solubilizing side chains of a polyester, a
polyacrylic, a polyether or a polyolefin including mixtures of such side
chains. The polyurethane dispersant is further characterized in that it
also comprises on average at least one group containing carbon to carbon
double bonds (unsaturation). The groups containing the carbon carbon
double bonds may be incorporated such that they are part of the vehicle
soluble chains or vehicle insoluble portion(s) of the dispersant. The
vehicle soluble or the vehicle insoluble portion of the dispersant can be
close to the backbone or pendant from the backbone, depending on the
vehicle and particle system chosen. In this disclosure, vehicle will
refer to the continuous phase in which the particulate is dispersed. It
may be water, organic solvents or blends thereof. In some preferred
embodiments, the vehicle soluble portions of the dispersant extend from
the dispersant backbone into the vehicle phase.

[0081]The invention also includes the dispersant materials themselves as
well as the composition in which they are used such as a coating, ink or
molding compound. According to the invention, there is provided a
non-aqueous composition comprising a particulate solid, an organic medium
and a polyurethane dispersant (in embodiment 1 having an essentially
linear backbone with laterally attached solvent solubilizing side chains)
of polyester, polyacrylic (especially a polyacrylate), polyether or
polyolefin including mixtures of such side chains (embodiment 1) or
essentially non-linear backbone with solvent-solubilizing side chains at
the termini and optionally laterally attached (embodiments 2 and 3). The
optimum choice of the solvent solubilizing side chain will be dependent
on the polarity of the vehicle (e.g., organic medium). In one embodiment,
the polyolefin is present and in another embodiment the polyolefin is
absent.

[0082]In one embodiment where non-aqueous vehicle is desirable, the
vehicle optionally contains 5 wt. % or less water, preferably less than 2
wt. %, more preferably less than 0.5 wt. % and most preferably no water.

[0083]The particulate solid present in the composition may be any
inorganic or organic solid material which is substantially insoluble in
the organic medium at the temperature concerned and which it is desired
to stabilise in a finely divided form therein.

[0084]Examples of suitable solids are pigments for solvent inks; pigments,
extenders and fillers for paints and plastics materials; dyes, especially
disperse dyes; optical brightening agents and textile auxiliaries for
solvent dyebaths, inks and other solvent application systems; solids for
oil-based and invert-emulsion drilling muds; dirt and solid particles in
dry cleaning fluids; particulate ceramic materials; magnetic materials
and magnetic recording media, fire retardants such as those used in
plastics materials and biocides, agrochemicals and pharmaceuticals which
are applied as dispersions in organic media.

[0085]A preferred particulate solid is a pigment from any of the
recognised classes of pigments described, for example, in the Third
Edition of the Color Index (1971) and subsequent revisions of, and
supplements thereto, under the chapter headed "Pigments". Examples of
inorganic pigments are titanium dioxide, zinc oxide, Prussian blue,
cadmium sulphide, iron oxides, vermilion, ultramarine and the chrome
pigments, including chromates, molybdates and mixed chromates and
sulphates of lead, zinc, barium, calcium and mixtures and modifications
thereof which are commercially available as greenish-yellow to red
pigments under the names primrose, lemon, middle, orange, scarlet and red
chromes. Examples of organic pigments are those from the azo, disazo,
condensed azo, thioindigo, indanthrone, isoindanthrone, anthanthrone,
anthraquinone, isodibenzanthrone, triphendioxazine, quinacridone,
perylene, diketopyrrolopyrrol (DPP), and phthalocyanine series,
especially copper phthalocyanine and its nuclear halogenated derivatives,
and also lakes of acid, basic and mordant dyes. Carbon black, although
strictly inorganic, behaves more like an organic pigment in its
dispersing properties. Preferred organic pigments are phthalocyanines,
especially copper phthalocyanines, monoazos, disazos, indanthrones,
anthranthrones, quinacridones, perylene, diketopyrrolopyrrol (DPP), and
carbon blacks.

[0087]In embodiments where the vehicle is an organic medium present in the
composition, it is preferably a polar organic medium or a substantially
non-polar aliphatic or aromatic hydrocarbon or halogenated hydrocarbon.
By the term "polar" in relation to the organic medium is meant an organic
liquid or resin capable of forming moderate to strong bonds as described
in the article entitled "A Three Dimensional Approach to Solubility" by
Crowley et al. in Journal of Paint Technology, Vol. 38, 1966, at page
269. Such organic media generally have a hydrogen bonding number of 5 or
more as defined in the above mentioned article.

[0088]Examples of suitable polar organic liquids are amines, ethers,
especially lower alkyl ethers, organic acids, esters, ketones, glycols,
alcohols and amides. Numerous specific examples of such moderately
strongly hydrogen bonding liquids are given in the book entitled
"Compatibility and Solubility" by Ibert Mellan (published in 1968 by
Noyes Development Corporation) in Table 2.14 on pages 39-40, and these
liquids all fall within the scope of the term polar organic liquid as
used herein.

[0090]The substantially non-polar, organic liquids which may be used,
either alone or in admixture with the aforementioned polar solvents, are
aromatic hydrocarbons, such as toluene and xylene, aliphatic hydrocarbons
such as hexane, heptane, octane, decane, petrolium distillates such as
white spirit, mineral oils, vegetable oils and halogenated aliphatic and
aromatic hydrocarbons, such as trichloro-ethylene, perchloroethylene and
chlorobenzene.

[0091]Examples of suitable polar resins, as the medium for the dispersion
form of the present invention, are film-forming resins such as are
suitable for the preparation of inks, paints and chips for use in various
applications such as paints and inks. Examples of such resins include
polyamides, and cellulose ethers, such as ethyl cellulose and ethyl
hydroxyethyl cellulose. Examples of paint resins include short oil
alkyd/melamine-formaldehyde, polyester/melamine-formaldehyde,
thermosetting acrylic/melamine-formaldehyde, long oil alkyd and
multi-media resins such as acrylic, epoxy, polyurethane and
urea/aldehyde.

[0092]The resin may also be an unsaturated polyester resin including the
so-called sheet molding compounds and bulk molding compounds which may be
formulated with reinforcing fibres and fillers. Such molding compounds
are described in DE 3,643,007 and the monograph by P. F. Bruins entitled
"Unsaturated Polyester Technology", Gordon and Breach Science publishers,
1976, pages 211 to 238.

[0093]If desired, the dispersions may contain other ingredients, for
example, resins (where these do not already constitute the organic
medium) binders, fluidizing agents (such as those described in
GB-A-1508576 and GB-A-2108143), anti-sedimentation agents, plasticizers,
levelling agents and preservatives.

[0094]The composition of particulate solid, polyurethane dispersant, and
optional vehicle typically contains from 5 to 95% by weight of the
particulate solid, the precise quantity depending on the nature of the
solid and the relative densities of the solid and the organic medium. For
example, a composition in which the solid is an organic material, such as
an organic pigment, preferably contains from 15 to 60% by weight of the
solid whereas a composition in which the solid is an inorganic material,
such as an inorganic pigment, filler or extender, preferably contains
from 40 to 90% by weight of the solid based on the total weight of
composition.

[0095]The composition is preferably prepared by milling the particulate
solid in the organic medium at a temperature which is not greater than
40° C. and especially not greater than 30° C. However, when
the solid is a crude phthalocyanine pigment such as copper
phthalocyanine, it is sometimes preferable to carry out the milling in an
organic liquid at a temperature between 50 and 150° C. since
greener and brighter shades may be obtained. This is particularly the
case where the organic liquid is a high boiling aliphatic and/or aromatic
distillate.

[0096]The composition may be obtained by any of the conventional methods
known for preparing dispersions. Thus, the solid, the organic medium and
the dispersant may be mixed in any order, the mixture then being
subjected to a mechanical treatment to reduce the particles of the solid
to an appropriate size, for example, by ball milling, bead milling,
gravel milling or plastic milling until the dispersion is formed.
Alternatively, the solid may be treated to reduce its particle size
independently or in admixture with either the organic medium or the
dispersant, the other ingredient or ingredients then being added and the
mixture being agitated to provide the dispersion.

[0097]If the composition is required in dry form, the liquid medium is
preferably volatile so that it may be readily removed from the
particulate solid by a simple separation means such as evaporation. It is
preferred, however, that the composition comprises the liquid medium.

[0098]If the dry composition consists essentially of the dispersant and
the particulate solid, it preferably contains at least 0.2%, more
preferably at least 0.5% and especially at least 1.0% dispersant based on
weight of the particulate solid. Preferably the dry composition contains
not greater than 100%, preferably not greater than 50%, more preferably
not greater than 20%, and especially not greater than 10% by weight
dispersant based on the weight of the particulate solid.

[0099]As described hereinbefore, the compositions are particularly
suitable for preparing millbases where the particulate solid is milled in
a liquid medium in the presence of both a particulate solid and a
film-forming resin binder.

[0100]Thus, according to a still further aspect of the invention there is
provided a millbase comprising a particulate solid, dispersant and a
film-forming resin.

[0101]Typically, the millbase contains from 20 to 70% by weight
particulate solid based on the total weight of the millbase. Preferably,
the particulate solid is not less than 30 and especially not less than
50% by weight of the millbase.

[0102]The amount of resin in the millbase can vary over wide limits but is
preferably not less than 10%, and especially not less than 20% by weight
of the continuous/liquid phase of the millbase. Preferably, the amount of
resin is not greater than 50% and especially not greater than 40% by
weight of the continuous/liquid phase of the millbase.

[0104]The compound having a polyether chain which is component (b) is
preferably poly(C2-3-alkylene oxide) which contains less than 60%
poly(ethylene oxide) and also preferably contains two groups which react
with isocyanates. Preferably, the amount of ethylene oxide is less than
40% and especially less than 20% by weight of the poly(C2-3-alkylene
oxide) chain. There are a number of ways of incorporating a polyether
lateral chain into an organic compound which contains these groups which
react with isocyanates.

[0105]Thus, in the case where the two groups which react with isocyanates
are both hydroxyl, a poly(C2-4-alkylene oxide) chain may be
conveniently attached by isocyanates having a functionality of two or
more. Compounds of this type are described in U.S. Pat. No. 4,794,147,
which involves sequentially reacting a mono-functional polyether with a
polyisocyanate to produce a partially capped isocyanate intermediate and
reacting the intermediate with a compound having at least one active
amino hydrogen and at least two active hydroxyl groups.

[0106]One preferred class of compound of this type may be presented by the
formula 1.

[0107]wherein

[0108]R is C1-20-hydrocarbyl group;

[0109]R1 is hydrogen, methyl or ethyl of which less than 60% is
hydrogen;

[0110]R2 and R3 are each, independently, C1-8-hydroxyalkyl;

[0111]Z is C2-4-alkylene;

[0112]X is --O-- or --NH--;

[0113]Y is the residue of a polyisocyanate;

[0114]m is from 2 to 150 and more preferably from 5 to 150;

[0115]p is from 1 to 4; and

[0116]q is 1 or 2.

[0117]R may be alkyl, aralkyl, cycloalkyl or aryl.

[0118]When R is aralkyl, it is preferably benzyl or 2-phenylethyl.

[0119]When R is cycloalkyl it is preferably C3-8-cycloalkyl such as
cyclohexyl.

[0120]When R is aryl it is preferably naphthyl or phenyl.

[0121]When R is alkyl, it may be linear or branched and preferably
contains not greater than 12, more preferably not greater than 8 and
especially not greater than 4 carbon atoms. It is especially preferred
that R is methyl or butyl.

[0122]The C2-4-alkylene radical represented by Z may be ethylene,
trimethylene, 1,2-propylene or butylene.

[0123]Preferably m is not less than 10. It is also preferred that m is not
greater than 100 and especially not greater than 80.

[0124]When q is 2 it is possible to link two different polyurethane
polymer chains but it is much preferred that q is 1.

[0125]When the polyisocyanate has a functionality which is greater than 2,
the compound which is component (b) may carry more than one poly(alkylene
oxide) chain. However, it is much preferred that p is 1, q is 1 and that
Y is the residue of a diisocyanate.

[0126]When R1 is a mixture of hydrogen and methyl and Z is
1,2-propylene and X is --NH-- the compound of formula 1 is a derivative
of polyalkylene glycol amine such as a Jeffamine® M polyether
available from Huntsman Corporation.

[0127]Preferably, R2 and R3 are both 2-hydroxyethyl.

[0128]It is also preferred that X is O.

[0129]Compounds of formula 1 are typically prepared by reacting a
mono-functional polyether with a polyisocyanate in an inert solvent such
as toluene at a temperature of from 50 to 100° C. until the
desired isocyanate value is reached optionally in the presence of an acid
catalyst. In one embodiment the acid catalyst is present and in another
embodiment the acid catalyst is absent. The temperature is then normally
reduced to between 40 and 60° C. when the requisite secondary
amine such as diethanolamine is added.

[0130]Useful compounds of formula 1 have been used as component (b) by
reacting a poly(propylene glycol) mono methyl ether, a poly(propylene
glycol) mono butyl ether or a Jeffamine® M series polyether having a
number average molecular weight of from 250 to 5,000 with a diisocyanate
such as TDI followed by diethanolamine.

[0131]A second preferred type of compound which can be used as component
(b) is of formula 2.

[0132]wherein

[0133]R, R1, Z and m are as defined hereinbefore;

[0134]R4 is an isocyanate reactive organic radical (group);

[0135]R5 is hydrogen or an isocyanate-reactive organic radical; and

[0136]n is 0 or 1.

[0137]The organic radical represented by R4 and R5 is an organic
radical containing an isocyanate-reactive group, such as --OH, --SH,
--COOH, --PO3H2 and --NHR6 in which R6 is hydrogen or
optionally substituted alkyl. As specific examples of isocyanate-reactive
radicals, there may be mentioned hydroxyalkyl, hydroxy alkoxy alkyl,
hydroxy (poly alkylene oxy) alkyl and hydroxy alkoxy carbonyl alkyl.

[0138]A preferred type of compound of formula 2 is where n is zero, Z is
1,2-propylene, R4 is --CH2CH2C(O)--O-(L)q'-H. Wherein
L is a hydrocarbyl group or alkoxy group, preferably L is a C2 to
C3 hydrocarbyl group or alkoxy group; and q' is 1 to 20, preferably
1 to 6 and most preferably 1. R5 is hydrogen. Compounds of this type
are obtainable or obtained by the Michael addition reaction of a
poly(alkylene oxide) monoalkyl ether monoamine and a hydroxy functional
acrylate such as 2-hydroxyethyl acrylate or hydroxypropyl acrylate. A
suitable source of poly(alkylene oxide) monoalkyl ether monoamine is the
Jeffamine® M series of polyethers available from Huntsman Corporation.
The reaction between the poly(alkylene oxide) mono alkylether monoamine
and 2-hydroxy functional acrylate is typically carried out in the
presence of air and at a temperature of 50 to 100° C., optionally
in the presence of a polymerization inhibitor such as hydroquinone or
butylated hydroxy toluene.

[0139]Another preferred type of compound of formula 2 is where n is zero,
Z is 1,2-propylene and R4 and R5 are both 2-hydroxyethyl.
Compounds of this type may be prepared by reacting a poly(alkylene oxide)
mono alkyl ether mono amine with ethylene oxide under acidic conditions.

[0140]Yet another preferred type of compound of formula 2 is where n is
zero, Z is 1,2-propylene and R4 is
--CH2CH2C(O)--O-(L)q'-H and R5 is hydrogen. Wherein L
is a hydrocarbyl group or alkoxy group, preferably L is a C2 to
C3 hydrocarbyl group or alkoxy group; and q' is 1 to 20, preferably
1 to 6 and most preferably 1. R5 is hydrogen. Compounds of this type
may be prepared by reacting a poly(alkylene oxide) mono alkyl ether mono
amine with about one stoichiometric equivalent of ethylene oxide under
acidic conditions.

[0141]Poly(alkylene oxide) monoalkyl ether monoamines may also be obtained
from reaction of a poly(alkylene oxide) monoalkyl ether with
acrylonitrile and hydrogen reduction according to the following general
scheme where R and R1 are as previously described.

[0142]A further preferred type of compound of formula 2 where n is zero, Z
is 1,3-propylene and R4 is 2-hydroxyethyl and R5 is hydrogen
may be obtained from reaction between poly(alkylene oxide) monoalkyl
ether monoamines of formula 2A and a hydroxy functional acrylate such as
2-hydroxyethyl acrylate or hydroxypropyl acrylate.

[0143]A third preferred type of compound which may be used as component
(b) is of formula 3:

[0144]wherein R, R1 and m are as defined hereinbefore and W is
C2-6-alkylene and especially ethylene. Compounds of this type are
obtainable or obtained by the Michael addition reaction of a hydroxy
amine and a poly(alkylene oxide) acrylate.

[0145]A fourth preferred type of compound which may be used as component
(b) is of formula 4.

[0146]wherein

[0147]R, R1, Z, m and n are as defined hereinbefore;

[0148]R7 represents hydrogen, halogen or C1-4 alkyl;

[0149]Q is a divalent electron withdrawing group; and

[0150]T is a divalent hydrocarbon radical which may carry substituents or
contain hetero atoms.

[0151]Examples of electron withdrawing groups which may be represented by
Q include --CO--, --COO--, --SO--, --SO2--, --SO2O-- and
--CONR8-- in which R8 is hydrogen or alkyl.

[0152]Hydrocarbon radicals which may be represented by T include alkylene,
arylene and mixtures thereof, said radicals optionally carrying
substituents or containing hetero-atoms. Examples of suitable radicals
represented by T are alkylene radicals containing from 1 to 12 carbon
atoms, oxyalkylene and polyoxyalkylene radicals of the formula
--(CH2CH(R1)O)x wherein R1 is as defined hereinbefore
and x is from 1 to 10,

phenylene and diphenylene radicals and other arylene radicals such as

[0153]wherein Y' is --O--, --S--, --CH2--, --CO-- or --SO2--

[0154]The compounds of Formula 4 are obtainable or obtained by the Michael
addition reaction of two moles of a poly(alkylene oxide) monoalkyl ether
monoamine with one mole of an unsaturated compound of the formula 5.

[0155]wherein Q, T and R7 are as defined hereinbefore.

[0156]Examples of unsaturated compounds of Formula 5 are especially
diacrylates and dimethacrylates wherein T is a C4-10-alkylene
residue, a polyoxyalkylene residue or an oxyethylated Bisphenol A
residue.

[0157]When component (b) is a polyester containing two groups which react
with isocyanates the polyester chain may be made by polymerizing one or
more hydroxy carboxylic acids or lactones thereof in the presence of
either a hydroxy or carboxy containing compound which acts as a
polymerization terminating moiety.

[0166]The polyester of Formulae 6 and/or 7 are typically made by reacting
one or more hydroxy carboxylic acids together with either a hydroxy
containing compound or carboxy containing compound at 50 to 250°
C. in an inert atmosphere and in the presence of an esterification
catalyst. Typical process conditions are described in WO 01/80987.

[0167]Compounds of Formula 6 may be reacted with a polyisocyanate and a
secondary amine under similar conditions described for the preparation of
compounds of Formula 1 to form polyester analogues.

[0168]Compounds of Formula 7 may be converted to a mono hydroxy compound
by reacting with a diol such as ethylene glycol or propylene glycol and
the resulting mono hydroxy derivative treated in similar manner to the
compound of Formula 6 in preparing polyester analogues to the polyether
of Formula 1.

[0169]A polyester which contains 2 functional groups which are reactive
towards an isocyanate at one end of the polyester may be prepared by the
Michael addition of an aminoalcohol with a polyester acrylate such as a
polycaprolactone acrylate with ethanolamine.

[0170]When component (b) is a compound which contains a poly(alk)acrylate
chain, it is preferably a poly(meth)acrylate containing either two
hydroxyl groups at one end of the acrylate chain or one hydroxyl and one
imino group at one end of the acrylate chain. The two hydroxyl groups or
the one hydroxyl and one imino group are preferably separated by 1 to 6
carbon atoms. Polyacrylates of this type are obtainable or obtained by
reacting a diol with an acrylate by, for example, Atom Transfer Radical
Polymerization as illustrated by the following reaction scheme. Reactions
of this type are disclosed in Macromolecules 1995, 28, 1721 and 1997, 30,
2190 and in J. Am. Chem. Soc. 1995, 117, 5614.

[0171]wherein R10 is C1-20-hydrocarbyl group and m is as defined
hereinbefore e.g. from 2 to 150 and more desirably from 5 to 150.

[0172]Alternatively, a dihydroxy functional poly(alk)acrylate may be
prepared by the free radical polymerization of a (meth)acrylate
monomer(s) in the presence of a dihydroxy functional chain transfer agent
such as thioglycerol according to the following reaction scheme.

[0173]The reaction is preferably carried out in the presence of an
initiator such as azo bis-(isobutyronitrile) (AIBN).

[0174]wherein R10 and m are as defined hereinbefore.

[0175]Monohydroxy functional polymer chains (polyether, polyester or
poly(alk)acrylate) may be converted to polymer chains containing both a
hydroxyl and imino group at one end by first reaction with an isocyanate
functional acrylate followed by a Michael addition of an alkanolamine to
the resulting adduct.

[0176]The following scheme illustrates such a synthetic conversion
starting with a monohydroxy functional polyester.

[0177]wherein R10 and m are as defined hereinbefore.

[0178]When component (b) is a compound which contains a polyolefin chain,
it is preferably a polyolefin containing either two hydroxyl groups at
one end of the polyolefin chain or one hydroxyl and one imino group at
one end of the polyolefin chain. It is preferred that the polyolefin
chain is polyisobutylene. Polyisobutylene chains which contain 2 or more
isocyanate reactive groups at one end of the chain may be prepared from
polyisobutenyl succinic anhydride (PIBSA). Reaction of PIBSA with an
alkyl diamine yields a polyisobutylene with a primary amine on one end.
This is illustrated for one type of PIBSA.

[0179]The primary amine ended polyisobutylene chain may be converted to
yield a product with two isocyanate reactive groups by Michael addition
of a hydroxy functional acrylate or addition of ethylene oxide in an
analogous way to that described above for poly(alkylene oxide) monoalkyl
ether monoamines.

[0180]As disclosed hereinbefore component (c) is a compound containing an
acid or amine group and at least two groups which react with isocyanates.
Preferably, the compound contains only two groups which react with
isocyanates since this restricts cross-linking between adjacent chains of
the dispersant. The acid group may be phosphonic, sulphonic or preferably
carboxylic, including mixtures thereof. Preferably, the groups of
component (c) which react with isocyanates are both hydroxy groups. A
preferred diol which is component (a) is a compound of formula 8.

[0181]wherein at least two of the groups R11, R12 and R13
are C1-6-hydroxy alkyl and the remainder is C1-6-hydrocarbyl
group, which may be linear or branched alkyl, aryl, aralkyl or
cycloalkyl, M is hydrogen or an alkaline metal cation, or quaternary
ammonium cation. Preferred examples of carboxylic acid components are
dimethylolpropionic acid (DMPA) and dimethylolbutyric acid (DMBA).

[0182]The acid containing compound which is component (c) may contain
other acid groups in addition to or instead of a carboxylic group(s),
such as phosphonic or sulphonic acid groups. An example of one such
compound is 1,3-benzene dicarboxylic
acid-5-sulpho-1,3-bis(2-hydroxyethyl) ester (EGSSIPA).

[0183]When component (c) carries a basic group in addition to the two
groups which react with isocyanates it is essential that the basic group
does not react with isocyanates. Basic groups of this type are aliphatic
tertiary amines, hindered aromatic amines and nitrogen heterocyclic
compounds which may be alicyclic or aromatic. Examples of hindered
aromatic amines are phenylamines having a steric hindering group in the 2
and/or 6-position. In one embodiment, it is desirable that the dispersant
comprise a nitrogen in a non-reactive amine (non-reactive with respect to
isocyanates) laterally attached to the polyurethane backbone such that
said nitrogen atom is separated by at least two atoms from the closest
atom on the backbone. Such non-reactive amines laterally attached are
thought to provide better anchoring to some particulate solids. The
non-reactive amine preferably is a tertiary amine. The non-reactive amine
may also be a quaternary ammonium salt. Specific examples of component
(c) having a basic group are N-methyl diethanolamine (NMDA),
N-phenyldiethanolanine (NPDA), N,N-bis(2-hydroxyethyl) isonicotinamide
(HEINA), 1,1'-{[3-(dimethylamino)-propyl]imino}bis-2-propanol and
compound 9 formed from the Michael addition of dimethylaminopropylamine
and 2-hydroxyethyl acrylate.

[0184]The formative compounds which are component (d) of the polyurethane
are preferably difunctional in respect of reactivity with isocyanates for
embodiment 1 although a small amount of higher functionality may be used
where a small amount of branching of the polyurethane polymer backbone is
desired. However, it is preferred that component (d) is difunctional.
Preferred reactive groups are amino and hydroxy and it is much preferred
that component (d) is a diamine or especially a diol. Component (d), if
present, is used primarily as a chain extender to alter the solubility of
the polyurethane polymer.

[0186]Examples of suitable diols are 1,6-hexanediol,
1,4-cyclohexanedimethanol (CHDM), 1,2-dodecanediol,
2-phenyl-1,2-propanediol, 1,4-benzene dimethanol, 1,4-butanediol and
neopentyl glycol. The diol may also be a polyether such as a poly
(C2-4-alkylene glycol), a polyester or polyacrylic diol. The
polyalkylene glycol may be a random or block (co)polymer containing
repeat ethyleneoxy, propyleneoxy or butyleneoxy groups, including
mixtures thereof.

[0187]As noted hereinbefore, it is preferred that the polyurethane polymer
backbone in embodiment 1 is essentially linear in character. However,
some small amount of branching may be unavoidable if there is a presence
of polyols or polyisocyantes with a functionality higher than 2 present
as an impurity in any of the components. The higher functionality polyols
or polyisocyanates are preferred in both embodiments 2 and 3.

[0188]As disclosed hereinbefore the chain terminating compound which is
component (e) is mono-functional with respect to the isocyanate. The
monofunctional group is preferably an amino or hydroxy group. Preferred
terminating groups are solubilizing poly(C2-4-alkylene) mono alkyl
ethers, poly(C2-4-alkylene) mono alkyl ether amines, polyesters,
polyacrylates and polyolefins similar to those used in the preparation of
the lateral side chain compounds which are component (b) of the
polyurethane.

[0189]An example of a monoisocyanate which acts as a chain terminating
compound (component f) is phenyl isocyanate. An example of a
monoisocyanate which contains a carbon to carbon double bond is
2-isocyanatoethyl methacrylate.

[0190]It is much preferred that the amount of component (D is zero.

[0191]Typical amounts of the aforementioned compounds from which the
polyurethane polymers are obtainable are 15-50% component (a), 10-80%
component (b), 0-24% component (c), 0-25% component (d), 0-50% component
(e) and 0-20% component (f), all based on the total weight of the
polyurethane polymer.

[0192]When component (e) is a monofunctional polyether, polyester,
poly(alk)acrylate or polyolefin the total amount of component (b) with
component (e) is preferably not less than 35% and where component (e) is
other than a monofunctional polyether, polyester or poly(alk)acrylate the
amount of component (b) is preferably not less than 35%.

[0193]Alternatively, the ratio of total number of isocyanate groups
provided by component (a) and optionally component (f) is greater that
the total number of isocyanate reactive groups provided by component (b)
and components (c), (d) and (e) when present. The resultant polyurethane
is then a prepolymer containing residual isocyanate functionality. This
prepolymer may then be reacted with other chain extenders such as
component (d) which conjoins different prepolymer chains and/or with
chain terminating compounds which are component (e), optionally prior to
or during dissolution in water or other polar solvent. In one embodiment
prepolymer is reacted with chain extenders prior to dissolution solvent.
In one embodiment prepolymer is reacted with chain extenders during
dissolution in solvent. In one embodiment prepolymer is reacted with
chain extenders prior to dissolution in the absence of water or other
solvent. In one embodiment the prepolymer may be reacted with chain
extenders in the absence of water.

[0194]The preparation of prepolymers can be useful since it is a means of
controlling viscosity during the preparation of the polyurethane polymer,
especially in circumstances where the reaction is carried out in the
absence of any solvent.

[0195]When a prepolymer is formed which contains isocyanate functionality,
chain extension may be carried out by water itself, or a polyol,
amino-alcohol, a primary or secondary aliphatic, alicyclic, aromatic,
araliphatic or heterocyclic polyamine especially a diamine, hydrazine or
a substituted hydrazine. This type of reaction is used more significantly
in embodiment 3.

[0197]The chain extension can be conducted at elevated, reduced or ambient
temperatures. Convenient temperatures are from about 5° C. to
95° C.

[0198]When employing a prepolymer in the preparation of the polyurethane
polymer, the amount of chain extender and chain terminating compound are
chosen to control the molecular weight of the polyurethane polymer. A
high molecular weight will be favoured when the number of
isocyanate-reactive groups in the chain extender is approximately
equivalent to the number of free isocyanate groups in the prepolymer. A
lower molecular weight of the polyurethane polymer is favoured by using a
combination of chain extender and chain terminator in the reaction with
the polyurethane prepolymer.

[0199]An inert solvent may be added before, during or after formation of
the polyurethane polymer/prepolymer in order to control viscosity.
Examples of suitable solvents are acetone, methylethylketone,
dimethylformamide, dimethylacetamide, diglyme, N-methylpyrrolidone,
butylacetate, methoxypropyl acetate, ethylacetate, ethylene and propylene
glycoldiacetates, alkyl ethers of ethylene and propylene glycol acetates,
toluene, xylene and sterically hindered alcohols such as t-butanol and
diacetone alcohol. Preferred solvents are ethyl acetate, butyl acetate,
methoxy propylacetate and N-methylpyrrolidone. The polyurethane may also
be formed in the presence of unsaturated monomers which include mono
functional and polyfunctional (meth)acrylates and styrenic monomers.

[0200]The number average molecular weight of the polyurethane polymer is
preferably not less than 2,000, more preferably not less than 3,000 and
especially not less than 4,000. It is also preferred that the number
average molecular weight of the polyurethane polymer is not greater than
50,000, more preferably not greater than 30,000 and especially not
greater than 20,000.

[0201]It is preferred for embodiment 1 and subsequent embodiments that the
amount of residual isocyanate functionality in the dispersant is less
than 0.1% and more preferably about zero.

EMBODIMENT 2

[0202]According to the invention, there is provided a non-aqueous
composition comprising a particulate solid, an organic medium and a
polyurethane dispersant having an essentially non-linear backbone with
laterally and or terminally attached solvent-solubilizing side chains of
a polyester, a polyacrylic, a polyether or a polyolefin including
mixtures of such side chains. The polyurethane dispersant is further
characterized in that it also comprises groups containing carbon carbon
double bonds in the same amounts as in embodiment 1. Similar to
embodiment 1 subsequent to polyurethane dispersant formation the double
bonds may be reacted with a crosslinking agent added to the composition
to crosslink (or chain extend) the dispersant around the particle
surface. Alternatively, the double bonds may be used to bond the
dispersant to a continuous phase in a molding composition, coating, or
ink that contains co-reactive continuous phase.

[0203]Embodiment 2 differs from embodiment 1 in that a small amount of
trifunctional or higher monomer in the urethane forming reactions are
used. This generates some branch points in the polyurethane backbone. The
trifunctional or higher reactants can be polyols, polyamines, or
polyisocyanates. For embodiment 2 it is preferred that the higher
functional reactants are polyols or polyamines. It is especially
preferred that they are polyols.

[0204]In embodiment 2, the proportions of mono, di and higher functional
components in the polyurethane synthesis are chosen such that a branched
polyurethane is produced as opposed to a fully crosslinked gel. It is
preferred that the number average molecular weight of the polyurethane is
not greater than 100,000. It is more preferred number average molecular
weight of the polyurethane is not greater than 70,000 and especially not
greater than 40,000. It is preferred that the number average molecular
weight of the polyurethane is at least 3,000. It is more preferred number
average molecular weight of the polyurethane is at least 5,000 and
especially at least 7,000. It is preferred that the average number of
branch points in the polyurethane is at least 1. It is more preferred
that the average number of branch points in the polyurethane is at least
2 and especially at least 3. It is also preferred that the average number
of branch points in the polyurethane is not greater than 20. It is more
preferred that the average number of branch points in the polyurethane is
not greater 12 and especially not greater 8. (The average number of
branch points in the polyurethane may be calculated from the molar
proportions of mono, di and higher functional compounds used to prepare
the polyurethane).

[0205]Embodiment 2 can be made according to the same general procedure for
forming embodiment 1 from components a-f with the following
substitutions.

[0206]For the (a) component (polyisocyanates), the functionality can be
from about 2 to about 10 (on average) and in one aspect from about 2 to
about 6. The additional isocyanates with functionality from about 2.5 to
about 6 or 10 are well known materials and more fully described in U.S.
Pat. No. 6,509,409 column 4, line 8, through column 7, line 18. The
isocyanates may be blends of different isocyanates or reaction products
of excess equivalents of isocyanates with polyols or polyamines to form
polyfunctional isocyanates. It is preferred that the average
functionality of polyisocyanate is from 2.0 to 2.5. It is more preferred
that the average functionality of polyisocyanate is from 2.0 to 2.2. It
is especially preferred that the average functionality of polyisocyanate
is about 2.0.

[0207]In embodiment 2, the presence of component (b), the lateral
solubilizing chains, is optional. It was considered essential in some
aspects of the invention to have lateral side chain solubilizing groups
to get the sufficient solubilizing chains in the dispersant.

[0208]It is preferred that one or more formative compounds (d) are
present. For the formative compounds of component (d), it is preferred
that the average number of groups that react with isocyanates is greater
than 2.0, more preferred greater than 2.05 and especially greater than
2.1. It is preferred that the average number of groups that react with
isocyanates is not more than 3.0. It is more preferred that that the
average number of groups that react with isocyanates is not more than 2.6
and especially not greater than 2.4.

[0209]At least one of the components (a) or (d) must have an average
functionality greater than 2.0.

[0210]The isocyanates of embodiment 2 can be prereacted with any of the
other components (such as a mono-functional or difunctional
solvent-solubilizing component) as there are generally less restrictions
on reaction conditions with components having a functionality above 2.

[0211]Embodiment 2 may look like the structure below which schematically
depicts a polyurethane wherein terminal solubilizing chains are present
with six branch points.

represents a residue of trifunctional formative compound (component d).
The other symbols and textures will have the same definitions as earlier
(on pages 3 and 4 of the application).

EMBODIMENT 3

[0212]The polyurethane dispersants disclosed by Byk (U.S. Pat. Nos.
4,647,647; 4,795,796; 4,942,213; and EP 154,678), Efka (U.S. Pat. Nos.
5,399,294; 5,425,900; and 5,882,393) and Avecia U.S. Pat. No. 6,509,409
can also be modified to include carbon to carbon double bonds in the same
amounts as embodiment 1 using the same reactants of embodiments 1 and 2
and optionally a slightly different reaction procedure. The starting
materials for embodiment 3 include the starting materials from
embodiments 1 and 2 along with the use of proportionately more urethane
forming monomers of higher than 2 functionality. The isocyanates ("a") in
embodiment 3 are the same as in embodiment 2, and typically in embodiment
3 the isocyanates on average have higher functionality than 2. The
compounds "b" of embodiment 3 are usually absent (meaning there is
usually monofunctional solvent-solubilizing chains from component (e))
The remainder of the components are very similar/interchangeable.

[0213]The polyurethane dispersants from Byk and Efka are characterized in
that they are made with polyisocyanates. For Byk patents functionality of
the polyisocyanate is ≧2.5 for Efka>2. Monofunctional solvent
solubilizing chains are on average a little less expensive than
difunctional solubilizing chains. The polyurethanes of embodiment 3 are
prepared in a 3 stage process.

[0214]Stage 1

[0215]A portion of the isocyanate groups of the isocyanate component "a"
are reacted with a polymer chain (polyester, polyether, polyacrylate or
polyolefin) which contains one group which reacts with isocyanates (the
solvent solubilizing chain of the dispersant) component (e).

[0216]Stage 2

[0217]A further portion of the isocyanate groups are reacted with
material(s) which contain 2 or more groups that react with isocyanates
(component "d") e.g. a diol such as a PEG. This serves to link together
several of the polyisocyanate derivatives to build molecular weight.
Optionally a compound having an amino group (component "c") or a chain
terminator (component "e") may be added at this stage. Any of components
b-f may contain carbon to carbon double bonds.

[0218]Stage 3

[0219]The residual isocyanates (if present) can then be reacted e.g. with
materials such as e and f of embodiments 1 and 2 which are monofunctional
with respect to reactivity with isocyanate to introduce other functional
groups e.g., tertiary or aromatic amines as in U.S. Pat. No. 4,647,647.

[0220]Incorporation of carbon to carbon double bonds may be achieved by
either

[0221](i) incorporating the double bond in the solvent solubilizing chain
introduced in stage 1 e.g. using a polymeric chain (e.g. polylactone)
with a hydroxy group at one end and an acrylate at the other, or

[0222](ii) Incorporating the carbon to carbon double bond using a mono
functional material with respect of isocyanate reactive groups (such as a
hydroxyl functional acrylic monomer like hydroxyethyl acrylate) such that
the double bond is closer to the anchoring core.

[0223]If a primary or secondary amine functional material is absent in
stage 3, it would be possible to add the hydroxy functional acrylate (or
similar) at any stage. However, if you do use such an amine the acrylate
will have to be added last to prevent reaction between the amine and the
activated double bond.

[0224]The invention thus relates to addition compounds or their salts
suitable as dispersing agents which contain reactive carbon carbon double
bonds. Such compounds are obtainable by the reaction of polyisocyanates,
hydroxyl compounds, compounds having Zerewitinoff-active hydrogen and at
least one basic group containing nitrogen, and optionally compounds
containing amine hydrogen, optionally in the presence of solvents and
optionally in the presence of reaction catalysts, characterized in that
they are obtainable by the reaction of polyisocyanates (a) having an
average functionality of from 2.5 to 6 with monohydroxyl compounds (e) of
the formula I

Y''--OH I

wherein Y'' has the following meanings:(i) aliphatic and/or cycloaliphatic
hydrocarbon groups with 8 to 30 carbon atoms in which the hydrogen atoms
may be partly replaced by halogens and/or aryl groups, (ii) aliphatic,
cycloaliphatic and/or aromatic groups with molecular weights of from 350
to 8000 which contain at least one --O-- and/or --COO-- group and in
which the hydrogen atoms may be partly replaced by halogens.

[0225]Optionally, the group Y'' contains at least one carbon to carbon
double bond. Desirably from 15 to 50%, preferably 20 to 40% and most
preferably 20 to 35% of the NCO groups are reacted. Reacting the
resulting reaction product in such a quantity with compounds (d) of the
formula II

G-(E)n' II

wherein E stands for --OH, --CO2H, --NH2 and/or --NHR (wherein R
represents an alkyl group having 1 to 4 carbon atoms) and n' stands for 2
or 3, and G represents an aliphatic, cycloaliphatic and/or aromatic group
with molecular weights of at the most 3000 which has at least 2 carbon
atoms and may contain --O--, --COO--, --CONH--, --S-- and/or --SO2--
groups, that a further 15 to 45%, preferably 20 to 40% and most
preferably 20 to 35% of the NCO groups of the polyisocyanates originally
put into the process are reacted but the sum of the degrees of NCO
reaction of reactions (a) and (b) amounts to at least 40% and at the most
75%, preferably 45 to 65% and most preferably 45 to 55%.

[0226]Optionally, the group G contains at least one carbon to carbon
double bond (c) reacting the resulting reaction product in such a
quantity with compounds (e) of the general formula III & IV

Z'-Q' III

T'-Q' IV

wherein Q' stands for --OH, --NH2, --NHR16 (wherein R16
stands for an alkyl group having 1 to 4 carbon atoms) or --SH, and Z' is
an aliphatic group with 2 to 10 carbon atoms containing at least one
tertiary amino group or a heterocyclic group containing at least one
basic ring nitrogen atom which carries no hydrogen atom, which
heterocyclic group may be attached to the group Q' by way of an alkylene
group having up to 10 carbon atoms, T' is a group which contains at least
one carbon to carbon double bond, that at least one molecule of the
compounds III and IV is available for each remaining isocyanate group
which has not been reacted in stages (a) and (b). The amount of compound
IV can vary from 0-100% of the amount needed to react with the remaining
isocyanate groups.

[0227]Reaction with compounds III and IV may occur sequentially or
together. However it is preferred that reaction of compound III occurs
first especially if T' contains an acrylate group and Q' in compound III
is --NH2 or --NHR16.

[0228]It is necessary that at least one or more of the compounds I, II or
IV contain a carbon to carbon double bond.

[0229]The invention also relates to the process for the preparation of the
addition compounds as described above.

[0230]The invention further relates to the use of the addition compounds
described above as dispersing agents.

Crosslinking the Dispersant for Encapsulation of Particle

[0231]The dispersant can be crosslinked or chain extended around the
particulate matter of the composition. The crosslinking or chain
extension is achieved by addition of a crosslinking agent which contains
functional groups which react with the double bonds contained within the
dispersant or by an addition polymerization reaction of those double
bonds.

[0232]If a crosslinking agent is used, it may be added at any stage of the
dispersion process, but it is preferred if it is added after the
particles have been dispersed in the liquid medium with the dispersant
already present. It is preferred that the average functionality of the
crosslinking agent is at least 2. It is especially preferred if the
average functionality of crosslinking agent is 3 or more. It is preferred
that the crosslinking agent it comprises amine functionality (primary
&/or secondary). It is preferred that the average functionality of the
total of primary and secondary amine groups in the crosslinker is 2 or
more. It is preferred that the crosslinker contains at least 2 primary
amine groups.

[0233]The amount of polyfunctional amine required in the composition will
depend on the amount of dispersant used and functionality of each with
respect to primary and secondary amine groups and reactive double bonds
respectively. It is preferred if the ratio of primary and secondary amine
groups to reactive double bonds is the range of 1 to 10 and 10 to 1. It
is more preferred if the range is 1 to 5 to 5 to 1. It is especially
preferred if the range is 1 to 3 to 3 to 1.

[0234]The polyfunctional amines for crosslinking can be from a wide
variety of materials and can be used as a single material or in mixtures
of such materials. They may be aliphatic or aromatic. There are numerous
specific examples. H2N(CH2)n.NH2 where n''=2 to 20,
specific examples include n''=2, n''=6, n''=12;
H2N(CH2CH2NH)m''CH2 CH2NH2 where m''=1 to
10 preferably 1 to 6; Spermidine, spermine;
N,N'-bis(3-aminopropyl)-ethylenediamine;
N,N'-bis(3-aminopropyl)-1,3-propanediamine; tris(2-aminoethyl)amine;
4,4'-methylenebis(cyclohexylamine); diaminocyclohexane; I isophorone
diamine; polyethyleneimine; Jeffamine D and T series polyether amines
(supplied by Huntsman).

Cocure of the Dispersant with a Reactive Binder System

[0235]The dispersants may be used in a composition containing a reactive
binder system which contains unsaturation. The reactive binder is cured
after the addition of the dispersion containing the dispersant. The
reactive binder may be liquid as in the case of a 100% UV cure ink or it
may be solid for instance for a UV cure powder coating.

[0236]The cure may be brought about by generation of free radicals either
thermally or from a radiation source. There are many initiators known to
those skilled in the art which can be used to generate radicals when
subjected to an increase in temperature. The choice of initiator is
governed by the desired operating temperature, solubility, desired rate
of cure etc. There are many examples of peroxides, hydroperoxides and azo
compounds that can be used. The generation of radicals from "thermal"
initiators can also be catalysed so that cure can take place at ambient
temperatures. One well known example is the use of tertiary amines to
catalyse the generation of radicals from peroxides. There are also a wide
range of initiators which may be used for UV cure. The choice among other
factors will depend on the wavelength of radiation used.

[0237]The binder systems may vary greatly in composition. The system will
contain reactive unsaturation with which the carbon to carbon double
bonds in the dispersant will coreact. These reactive groups may be
present on monomeric, oligomeric and/or polymeric components in the
reactive binder system. The types of reactive double bonds in the binder
may be drawn from acrylate, methacrylate, or styrenic. It will be usual
that the reactive binder systems will contain a portion of material which
contains a reactive functionality of >2 to enable formation of a cross
linked network.

[0238]There are a very wide range of monomers and oligomers available with
mono, di and polyfunctionality of reactive double bonds. The oligomers
include unsaturated polyesters, epoxy acrylates, urethane acrylates,
polyester acrylates, polyether acrylates and acrylated acrylics.

[0240]In sheet and bulk molding compounds, the most common type of
reactive binder systems are unsaturated polyester in combination with
styrene monomer. The binder is formulated with other components well
known to those skilled in the art such as fibres, release agents.
Therefore, co-reactivity of the carbon to carbon double bond in the
dispersant with styrene is essential for use in these systems.

[0241]For reactive curing systems it is particularly desirable to minimize
the VOC content of the final formulation. Therefore, it is preferable for
the dispersants to be delivered either in a minimum of organic solvent,
as 100% active, or dissolved in a reactive component of the curing
system.

Preparation of Intermediates

[0242]The preparation of the intermediates and dispersants described below
was carried out on more than one occasion. Some intermediate preparations
were repeated to provide more material for testing.

[0243]Intermediate A--Dihydroxy polyester

[0244]1-Dodecanol (32.1 parts, 0.0.172 mol), ε-caprolactone
(186.76 parts, 1.631 mol) and δ-valerolactone (60.35 parts, 0.603
mol) were stirred together under nitrogen at 180° C. Zirconium
butoxide catalyst (1.34 parts) was added and the reactants were stirred
under nitrogen for ca. 20 hours at 180° C. After cooling to
20° C., the polyester was obtained as a waxy solid. This is
polyester 1.

[0245]Tolylene diisocyanate (26.88 parts,) was added to a reaction vessel
with methoxypropyl acetate (100 parts) heated to 40° C. Polyester
1 (250 parts) dissolved in methoxypropyl acetate (100 parts) was added
over 2 hours with stirring at 50-60° C. The reaction was monitored
using online infrared detection. Reaction was continued at 60° C.
for a further 30 minutes after the end of the feed. The temperature was
raised to 70° C. and reaction continued for a further 1 hour. At
this stage the infrared peak associated with the NCO group was showing no
further decrease in size. The reactants were then cooled to 7° C.
with an external ice bath and a solution of diethanolamine (16.22 parts)
in methoxypropyl acetate (32 parts) was added causing a temperature rise
to 21° C. The reaction was continued with stirring at 35°
C. until no isocyanate remained.

[0249]1-Dodecanol (93.15 parts), ε-caprolactone (399.5 parts) and
δ-valerolactone (350.4 parts) were stirred together under nitrogen
at 150° C. Zirconium butoxide catalyst (4.0 parts) was added and
the reactants were stirred under nitrogen for 20 hours at 180° C.
After cooling to 20° C., the polyester obtained was a viscous
liquid. This is polyester 2.

[0250]Tolylene diisocyanate (82.63 parts) was added to a reaction vessel
and heated to 50° C. under nitrogen. Polyester 2 (800 parts) was
added over 2 hrs with agitation at 50-60° C. The reaction was
continued with stirring at 60° C. for 1 hour. The reactants were
then cooled to 20° C. and diethanolamine (49.88 parts) was added.
The reaction was continued with stirring at 35° C. until no
isocyanate remained.

[0251]Intermediate D

[0252]Hydroxyethyl methacrylate (80.0 parts), ε-caprolactone
(666.73 parts) and δ-valerolactone (215.44 parts), 4-methoxy phenol
(0.96 parts), tin(II) chloride (0.05 parts) were stirred together under
an air atmosphere at 125° C. The reaction was allowed to continue
at this temperature for 20 hours. After cooling to 20° C., the
polyester was obtained as a waxy solid.

[0253]Intermediate E

[0254]1-Dodecanol (114.16 parts), s-caprolactone (666.73 parts) and
δ-valerolactone (215.44 parts) were stirred together under nitrogen
at 150° C. Zirconium butoxide catalyst (4.0 parts) was added and
the reactants were stirred under nitrogen for 20 hours at 180° C.
After cooling to 20° C., the polyester was obtained as a waxy
solid.

[0255]Intermediate F

[0256]Tolylene diisocyanate (48.02 parts) was added to a reaction vessel
heated to 50° C. under nitrogen. Intermediate D (400 parts) was
added over 2 hrs with agitation at 50-60° C. The reaction was
continued with stirring at 60° C. for 1 hour. The reactants were
then cooled to 20° C. and diethanolamine (28.99 parts) was added.
The reaction was continued with stirring at 35° C. until no
isocyanate remained. Di-tert-butyl-4-methylphenol (0.24 parts) was then
added.

[0257]Intermediate G

[0258]Hydroxyethyl acrylate (71.38 parts), s-caprolactone (666.73 parts)
and δ-valerolactone (215.44 parts), 4-methoxy phenol (0.95 parts),
tin(II) chloride (0.047 parts) were stirred together under an air
atmosphere at 125° C. The reaction was allowed to continue at this
temperature for 20 hours. After cooling to 20° C., the polyester
was obtained as a waxy solid.

[0259]Intermediate H

[0260]1-Dodecanol (64.1 parts) and ε-caprolactone (509.97 parts)
were stirred together under nitrogen at 150° C. Zirconium butoxide
catalyst (2.9 parts) was added and the reactants were stirred under
nitrogen for 20 hours at 180° C. After cooling to 20° C.,
the polyester was obtained as a waxy solid. This is Polyester 3.

[0261]Tolylene diisocyanate (41.71 parts) was added to a reaction vessel
heated to 50° C. under nitrogen. Polyester 3 (400 parts) was
warmed to 50° C. in an oven then added to the reaction vessel over
2 hrs with agitation at 50-60° C. The reaction was continued with
stirring at 60° C. for 1 hour. The reactants were then cooled to
20° C. and diethanolamine (25.18 parts) was added. The reaction
was continued with stirring at 35° C. until no isocyanate
remained.

[0262]In the following examples the molecular weight of the dispersants
produced were characterized by size exclusion chromatography. The number
average molecular weight (Mn) and weight average molecular weight (Mw)
values were determined relative to polystyrene standards. For
polymerizations carried out in solvent the final solids content of the
solution was determined by gravimetric analysis.

[0263]Dispersant 1

[0264]Dimethylolpropionic acid (7.4 parts, and often referred to as
2,2-bis(hydroxymethyl)propionic acid), 1,4-cyclohexane dimethanol (7.88
parts), Intermediate B (150.0 parts), 2-hydroxyethyl acrylate (4.2
parts), and ethyl acetate (195 parts) were added to a round bottomed
flask and heated with agitation to 70° C. under a nitrogen
atmosphere. Dibutyltindilaurate (0.1 parts) in ethyl acetate (10 parts)
was added. Tolylene diisocyanate (34.62 parts) was added to the reaction
vessel dropwise over a period of 30 minutes maintaining the temperature
at 70-75° C. Reaction was allowed to continue at this temperature
for a further 28 hours when only a trace of isocyanate was detectable by
infrared analysis. Ethanol (10 parts) were added and butylated hydroxyl
toluene (BHT) (0.02 parts) added as a free radical inhibitor.

[0265]Solids content was adjusted to 50 wt. % by addition of ethyl acetate
to compensate for small solvent evaporation losses (Mn=12,300 and
Mw=24,900).

[0266]Comparative Dispersant α

[0267]This polyurethane is very similar to example 1 but does not contain
any carbon to carbon double bonds. Dimethylolpropionic acid (7.8 parts),
14-cyclohexane dimethanol (10.27 parts), Intermediate B (144.0 parts)
1-butanol (2.93 parts) and ethyl acetate (180 parts) were added to a
round bottomed flask and heated with agitation to 70° C. under a
nitrogen atmosphere. Dibutyltindilaurate (0.1 parts) in ethyl acetate (10
parts) was added. Tolylene diisocyanate (37.83 parts) was added to the
reaction vessel dropwise over a period of 45 minutes maintaining the
temperature at 70-75° C. Reaction was allowed to continue at this
temperature for a further 28 hours when only a trace of isocyanate was
detectable by infrared analysis. (Mn=12,300 and Mw=22,400).

Pigment Dispersion Performance

[0268]Dispersion Formulation:

[0269]Dispersions were prepared by adding dispersant 1 (8.0 parts) to
methoxypropyl acetate (22 parts) in a 4 oz glass jar. Black pigment (20
parts, Printex 35, ex Degussa) was added and the mixture was gently
stirred to wet out the pigment. Glass beads (3 mm diameter, 125 parts)
were added to the jar. The jar was placed in a Scandex disperser model
200-K and the contents milled by oscillatory shaking for 2 hours. This is
Millbase 1.

[0270]A solution of tetraethylpentamine (TEPA) (5.88 parts) in ethyl
acetate/ethanol (3/1) (100 parts) was prepared. The TEPA solution (0.063
parts) was added to a portion of Millbase 1 (5 parts) together with ethyl
acetate/ethanol (3/1) (0.44 parts). This is Millbase 1A. Ethyl
acetate/ethanol (3/1) (0.50 parts) was added to a portion of Millbase 1
(5 parts). This is Millbase 1B. The Millbases 1A and 1B (0.5 parts) were
let down into a nitrocellulose resin, NC DLX 3/5, (1.5 parts, ex Nobel
Enterprises). Millbases and inks were prepared in the same way using
Dispersant a to produce Millbase α1 and Inks α1A and
α1B.

[0271]A portion of the resulting inks were drawn down on to black and
white card using a number 3 K-bar. A simple visual assessment was made of
the draw downs based on hiding power, jetness and gloss with a scoring
system of 1 to 5. A score of 5 indicating the best performance. A control
experiment with no dispersant gave a let down with quality equal to 1.

[0272]The remaining portion of the inks was stored for 2 weeks at
52° C. The stored inks were drawn down on to black and white in
the same away and assessed to see if there had been any change on
storage.

[0273]Only for the ink 1A was there no reduction in quality of the
drawdown after 2 weeks storage of the ink at 52° C. For ink 1A
both the dispersant used contained carbon to carbon double bonds and TEPA
was present in the formulation.

[0280]To demonstrate that these materials will be reactive in a sheet
molding compound type formulation the coreactivity with styrene was
investigated.

[0281]Copolymerization of dispersants 2, 3 and 4 with styrene.

[0282]Styrene (10 parts), dispersant (ca. 21 parts ca. 50 wt. % in ethyl
acetate) and toluene (10 g) were charged to a schlenk tube under a
nitrogen atmosphere followed by 2,2'-azobis(2-methylpropionitrile) (0.1
parts). The contents were heated for 20 hours at 70° C. then
cooled to room temperature. In each case the product of the reaction was
gel consistent with a cross linking reaction having occurred between the
dispersant and styrene.

[0283]To show that gellation did not occur in the absence of the
dispersants a homo-polymerization of styrene was carried out under
similar conditions. Styrene (10 parts) and toluene (20 parts) were
charged to a schlenk tube under a nitrogen atmosphere followed by
2,2'-azobis(2-methylpropionitrile) (0.1 parts). The contents were heated
for 20 hours at 70° C. then cooled to room temperature yielding a
solution of polystyrene as a clear pourable liquid.

[0287]Intermediate B (32.64 parts), cyclohexane dimethanol (5.30 parts),
poly(propylene glycol) methacrylate (3.66 parts), dibutyltin dilaurate
(0.05 parts) and methoxypropyl acetate (51.66 parts) were added to a
round bottom flask and heated with agitation to 70° C. under a
nitrogen atmosphere. Tolylene diisocyanate (10.0 parts) was added drop
wise over a period of 30 minutes maintaining the temperature at
70-75° C. The reaction was allowed to continue at this temperature
for a further 4 hours when only a trace of isocyanate remained.
(Mn=11,400 and Mw=34,600).

[0288]Dispersant 7

[0289]Intermediate B (74.00 parts), hexane diol (7.33 parts),
hydroxylethyl acrylate (2.25 parts), dibutyltin dilaurate (0.1 parts) and
methoxypropyl acetate (102.25 parts) were added to a round bottom flask
and heated with agitation to 70° C. under a nitrogen atmosphere.
Tolylene diisocyanate (18.57 parts) was added drop wise over a period of
30 minutes maintaining the temperature at 70-75° C. The reaction
was allowed to continue at this temperature for a further 4 hours when
only a trace of isocyanate remained. Di-tert-butyl-4-methylphenol (0.01
parts) was then added. Solids content was 49 wt. % (Mn=11,800 and
Mw=41,100).

[0290]Dispersant 8

[0291]Intermediate A (32.64 parts), cyclohexane dimethanol (5.07 parts),
caprolactone 2-(methacryloyloxyethyl)ester (2.61 parts), dibutyltin
dilaurate (0.05 parts) and methoxypropyl acetate (50.61 parts) were added
to a round bottom flask and heated with agitation to 70° C. under
a nitrogen atmosphere. Tolylene diisocyanate (10.24 parts) was added drop
wise over a period of 30 minutes maintaining the temperature at
70-75° C. The reaction was allowed to continue at this temperature
for a further 4 hours when only a trace of isocyanate remained. Solids
content was 50 wt. % (Mn=7,800 and Mw=26,700).

[0292]Dispersant 9

[0293]Intermediate A (19.72 parts), N-methyldiethanolamine (2.85 parts),
hydroxyethyl methacrylate (0.46 parts), dibutyltin dilaurate (0.03 parts)
and methoxypropyl acetate (29.46 parts) were added to a round bottom
flask and heated with agitation to 70° C. under a nitrogen
atmosphere. Tolylene diisocyanate (6.40 parts) was added drop wise over a
period of 30 minutes maintaining the temperature at 70-75° C. The
reaction was allowed to continue at this temperature for a further 4
hours when only a trace of isocyanate remained. Solids content was 50 wt.
% (Mn=5,300 and Mw=12,200).

[0294]Dispersant 10

[0295]Tolylene diisocyanate (49.75 parts) was added to a round bottom
flask under a nitrogen atmosphere. With agitation, intermediate B (192.40
parts), hexane diol (9.29 parts), N-methyldiethanolamine (8.16 parts),
hydroxyethyl methacrylate (12.39 parts) and di-tert-butyl-4-methylphenol
(0.15 parts) were added over a period of 30 minutes and the contents
exothermed to 50-55° C. The reaction was heated to 70-75°
C. for a further 1.5 hours. Dibutyltin dilaurate (0.3 parts) was then
added and the contents maintained at 70-75° C. for 20 hours.
Hydroxyethyl methacrylate (1.2 parts) was then added and the
polymerisation maintained at 70-75° C. for 30 minutes when only a
trace of isocyanate remained. (Mn=6,400 and Mw=18,000).

[0296]Dispersant 11

[0297]Tolylene diisocyanate (19.42 parts) was added to a round bottom
flask under a nitrogen atmosphere. With agitation, intermediate C (74
parts), N-methyldiethanolamine (6.58 parts), hydroxyethyl acrylate (4.32
parts) and di-tert-butyl-4-methylphenol (0.05 parts) were added over a
period of 30 minutes and the contents exothermed to 50-55° C. The
reaction was heated to 70-75° C. for a further 4 hours until only
a trace of isocyanate remained. (Mn=4,200 and Mw=15,700).

[0298]Dispersant 12

[0299]Intermediate B (228.00 parts) and 2,2-bis(hydroxymethyl)propionic
acid (19.23 parts) were added to a round bottom flask with agitation
under a nitrogen atmosphere. Tolylene diisocyanate (52.47 parts) was then
added and the temperature exothermed to 40-45° C. Hydroxyethyl
methacrylate (13.07 parts), dibutyltin dilaurate (0.3 parts) and
di-tert-butyl-4-methylphenol (0.16 parts) were then added and the
contents heated to 70-75° C. The reaction was maintained at
70-75° C. for 20 hrs until no isocyanate remained. (Mn=8,400 and
Mw=17,300).

[0300]Dispersant 13

[0301]Intermediate B (60.0 parts), 2,2-bis(hydroxymethyl)propionic acid
(3.0 parts), hexane diol (10.37 parts), Intermediate D (40.16 parts),
dibutyltin dilaurate (0.1 parts), di-tert-butyl-4-methylphenol (0.14
parts) and methoxypropyl acetate (140.16 parts) were added to a round
bottom flask and heated with agitation to 70° C. under a nitrogen
atmosphere. Tolylene diisocyanate (26.53 parts) was added drop wise over
a period of 30 minutes maintaining the temperature at 70-75° C.
The reaction was allowed to continue at this temperature for a further 20
hours when only a trace of isocyanate remained. (Mn=6,900 and Mw=24,500).

[0302]Dispersant 14

[0303]Intermediate F (71.0 parts), N-methyldiethanolamine (3.0 parts),
hexane diol (5.41 parts), Intermediate E (18.14 parts), dibutyltin
dilaurate (0.1 parts), di-tert-butyl-4-methylphenol (0.1 parts) and ethyl
acetate (118.14 parts) were added to a round bottom flask and heated with
agitation to 70° C. under a nitrogen atmosphere. Tolylene
diisocyanate (20.49 parts) was added drop wise over a period of 30
minutes maintaining the temperature at 70-75° C. The reaction was
allowed to continue at this temperature for a further 3 hours when only a
trace of isocyanate remained. Solids content was 55 wt. % (Mn=6,700 and
Mw=22,000).

[0304]Dispersant 15

[0305]Intermediate F (60.0 parts), hexane diol (11.79 parts), Intermediate
D (78.0 parts), dibutyltin dilaurate (0.1 parts),
di-tert-butyl-4-methylphenol (0.18 parts) and butyl acetate (178.0 parts)
were added to a round bottom flask and heated with agitation to
70° C. under a nitrogen atmosphere. Tolylene diisocyanate (28.11
parts) was added drop wise over a period of 30 minutes maintaining the
temperature at 70-75° C. The reaction was allowed to continue at
this temperature for a further 3 hours when only a trace of isocyanate
remained. Solids content was 50 wt. % (Mn=5,200 and Mw=9,200).

[0306]Dispersant 16

[0307]Intermediate C (60.0 parts), N-methyldiethanolamine (8.0 parts),
hexane diol (4.15 parts), Intermediate G (76.31 parts),
di-tert-butyl-4-methylphenol (0.1 parts) were added to a round bottom
flask and heated with agitation to 70° C. under a nitrogen
atmosphere. Tolylene diisocyanate (27.75 parts) was added drop wise over
a period of 30 minutes maintaining the temperature at 70-75° C.
The reaction was allowed to continue at this temperature for a further 2
hours when only a trace of isocyanate remained. (Mn=7,300 and Mw=19,800).

[0308]Dispersant 17

[0309]Intermediate H (126.14 parts), 2,2-bis(hydroxymethyl)propionic acid
(4.1 parts), hexane diol (4.0 parts), hydroxyethyl methacrylate (7.86
parts), di-tert-butyl-4-methylphenol (0.05 parts), dibutyltin dilaurate
(0.1 parts) and ethyl acetate (50.8) were added to a round bottom flask
and heated with agitation to 70° C. under a nitrogen atmosphere.
Tolylene diisocyanate (22.80 parts) was added drop wise over a period of
30 minutes maintaining the temperature at 70-75° C. The reaction
was allowed to continue at this temperature for a further 20 hours when
only a trace of isocyanate remained. The majority of solvent was then
removed on a rotary evaporator. The material was transferred to a metal
tray and the product further dried in a vacuum oven. (Mn=1600 and
Mw=10,600).

[0310]Dispersant 18

[0311]Tolylene diisocyanate (52.19 parts) was added to a round bottom
flask under a nitrogen atmosphere. With agitation, intermediate B (210
parts), 1,1'-{[3-(dimethylamino)-propyl]imino}bis-2-propanol (37.81
parts), hydroxyethyl acrylate (6.33 parts) and
di-tert-butyl-4-methylphenol (0.31 parts) were added over a period of 30
minutes and the contents exothermed to 50-55° C. The reaction was
heated to 70-75° C. for a further 4 hours until only a trace of
isocyanate remained. Solids content was 52.0 wt. % (Mn=6,700 and
Mw=20,900).

[0312]Dispersant 19

[0313]Dispersant 18 (300 parts) was added to a round bottom flask and
heated to 70° C. under nitrogen with agitation. Benzyl chloride
(9.4 parts) and methoxypropyl acetate (9.4 parts) was then added and the
reaction maintained at 70° C. for 20 hours. The product was a
viscous liquid. Solids content was 53.0 wt. %.

[0314]Dispersant 20

[0315]Tolylene diisocyanate (26.48 parts) was added to a round bottom
flask under a nitrogen atmosphere. With agitation, intermediate C (105
parts), 1,1'-{[3-(dimethylamino)-propyl]imino}bis-2-propanol (18.52
parts) and hydroxyethyl methacrylate (3.6 parts) were added over a period
of 30 minutes and the contents exothermed to 50-55° C. The
reaction was heated to 70-75° C. for a further 4 hours until only
a trace of isocyanate remained. (Mn=5,500 and Mw=22,400).

[0316]Dispersant 21

[0317]Hexanediol (13.9 parts), Intermediate B (207.0 parts),
2,2-bis(hydroxymethyl)propionic acid (15.45 parts), hydroxyethyl
methacrylate (8.61 parts), butylated hydroxytoluene (0.001 parts) and
methoxypropyl acetate (308.6 parts) were stirred under air at ca.
23° C. Dibutyltin dilaurate (0.30 parts) was then added. Tolylene
diisocyanate (63.35 parts) charged to the reaction mixture over ca. 5
mins. resulting in a small exotherm. The reaction mixture was then heated
to 70-72° C. and stirred under air for a further 20.5 hours until
only a slight trace of isocyanate remained by infra red analysis. Solids
content was 50.8 wt. % (Mn=6,900 and Mw=21,400).

[0318]Dispersant 22

[0319]Hexanediol (13.08 parts), Intermediate A (414.0 parts, 50 wt %
solution in methoxypropyl acetate), 2,2-bis(hydroxymethyl)propionic acid
(15.45 parts), hydroxyethyl acrylate (7.78 parts), Butylated
hydroxytoluene (0.001 parts) and methoxypropyl acetate (100.8 parts) were
stirred under air at ca. 24° C. Dibutyltin dilaurate (0.30 parts)
was then added. Tolylene diisocyanate (64.17 parts) was charged to the
reaction mixture over ca. 18 mins. resulting in an exotherm to 56°
C. The reaction mixture was then heated to 70-73° C. and stirred
under air for a further ca. 19.3 hours until no isocyanate remained by
infra red analysis. Solids content was 49.6 wt. % (Mn=4,200 and
Mw=13,200).

[0320]Dispersant 23

[0321]Hexanediol (12.03 parts), Intermediate A (414.0 parts 50 wt. %
solution in methoxypropyl acetate), NMDA (15.45 parts), hydroxyethyl
methacrylate (8.86 parts), butylated hydroxytoluene (0.001 parts) and
methoxypropyl acetate (101.9 parts) were stirred under air at ca.
22° C. Dibutyltin dilaurate (0.30 parts) was then added. Tolylene
diisocyanate (65.22 parts) was charged to the reaction mixture over ca. 8
mins. resulting in an exotherm to 54° C. The reaction mixture was
then heated to 70-73° C. and stirred under air for a further ca. 3
hours until no isocyanate remained by infra red analysis. Solids content
was 48.8 wt. % (Mn=7,200 and Mw=22,500).

[0338]In the absence of a dispersant in the formulations, formed a thick
inhomogeneous immovable gel with regions in which the pigment was not
wetted.

[0339]In the presence of dispersants, the pigment milled to form a paste.
The viscosity of the paste has been determined in the table below by
determining the freedom of the glass beads to move throughout the mill
base. In all cases the pigment was wetted out and a homogeneous
dispersion formed.

[0341]For dispersion D17, the viscosity of the dispersion was measured on
a TA Instruments AR2000 Rheometer. Approximately 1 ml of the dispersion
was applied to the peltier plate and the measuring geometry (a 40 mm
2° steel cone) was then lowered onto the sample. A shear rate
sweep of 0.04 to 2000 s-1 was then applied to the sample whilst
maintaining a constant temperature of 25° C. The viscosity of the
dispersion was as shown in the following table.

[0342]The presence of reactive double bonds in the dispersant has been
shown to have a beneficial effect in a model UV curing system.

[0343]Comparison was made between a formulation containing dispersant 1 of
this invention and comparative dispersant a with a similar composition
except that it does not contain reactive double bonds. Formulations UV1
and UVα were prepared from the following materials.

[0344]Films were of UV1 and UVα were drawn down onto glass panels
using a K bar number 0. The coated panels were cured in a Fusion Systems
UV apparatus by being passed under 10'' long D bulb (with a power rating
of 120 watts/cm) at a speed of ca. 40 m/min.

[0345]After 7 passes under the lamp the film from formulation UV1 had a
Koenig hardness of 31 seconds. The comparative coating from formulation
UVα only had a Koenig hardness of 24 seconds.

[0346]Another film coated similarly from formulation UV1 achieved a Koenig
hardness of 26 seconds after five passes under the UV lamp.

[0347]These observations demonstrate that coating from UV1 produced of a
harder film after an equivalent cure time or a required a shorter cure
time to achieve the same hardness relative to the formulation containing
the comparative dispersant α without reactive double bonds.

[0348]Blue UV Ink Formulations

[0349]Dispersions were prepared by adding the materials detailed in the
following table to a 4 oz. glass jar in the order listed.

[0350]The mixture was gently stirred to wet out the pigment. 125 parts of
3 mm diameter glass beads were added to the jar. The jar was placed in a
Scandex disperser model 200-K and the contents milled by oscillatory
shaking for 4 hours.

[0351]Blue UV inks were then prepared by adding 3.21 parts of each of the
dispersions to a mixture of the following components.

[0352]The resulting inks were drawn down onto Leneta black and white card
using an automatic film applicator fitted with a number 0 K bar. The
coatings were cured in a Fusion Systems UV apparatus by being passed 4
times under 10'' long D bulb (with a power rating of 120 watts/cm) at a
speed of ca. 40 m/min.

[0353]The gloss and haze of the coatings were measured with a gloss and
haze meter. The ink containing dispersants produced a glossier coatings
with much higher color strength than the comparative ink without a
dispersant present.

[0355]The mixture was gently stirred to wet out the pigment. 125 parts of
3 mm diameter glass beads were added to the jar. The jar was placed in a
Scandex disperser model 200-K and the contents milled by oscillatory
shaking for 4 hours.

[0356]Yellow UV inks were then prepared by adding 3.21 parts of each of
the dispersions to a mixture of the following components.

[0357]The resulting inks were drawn down onto Leneta black and white card
using an automatic film applicator fitted with a number 0 K bar. The
coatings were cured in a Fusion Systems UV apparatus by being passed 4
times under 10'' long D bulb (with a power rating of 120 watts/cm) at a
speed of ca. 40 m/min.

[0358]The gloss and haze of the coatings were measured with a gloss and
haze meter. The ink containing dispersants produced a glossier coatings
with higher color strength than the comparative ink without a dispersant
present.

[0359]Dispersions and mill bases made from the composition of the
invention are particularly suitable for use in paints, including high
solids paints, solvent based inks, especially flexographic, gravure, and
screen inks, uv cure inks, color filter layers for display screen
equipment, thermosetting resin compositions such as sheet molding
compounds, bulk molding compounds or gel coats and non-aqueous ceramic
processes.

[0360]The dispersants may also be used for dispersing particulate matter
including pigments in powder coating formulations particularly powder
coatings which are to be cured by radiation curing.

[0361]Each of the documents referred to above is incorporated herein by
reference. Except in the Examples, or where otherwise explicitly
indicated, all numerical quantities in this description specifying
amounts of materials, reaction conditions, molecular weights, number of
carbon atoms, and the like, are to be understood as modified by the word
"about." Unless otherwise indicated, each chemical or composition
referred to herein should be interpreted as being a commercial grade
material which may contain the isomers, by-products, derivatives, and
other such materials which are normally understood to be present in the
commercial grade. However, the amount of each chemical component is
presented exclusive of any solvent or diluent oil, which may be
customarily present in the commercial material, unless otherwise
indicated. It is to be understood that the upper and lower amount, range,
and ratio limits set forth herein may be independently combined.
Similarly, the ranges and amounts for each element of the invention may
be used together with ranges or amounts for any of the other elements. As
used herein, the expression "consisting essentially of" permits the
inclusion of substances that do not materially affect the basic and novel
characteristics of the composition under consideration.

[0362]While the invention has been explained in relation to its preferred
embodiments, it is to be understood that various modifications thereof
will become apparent to those skilled in the art upon reading the
disclosure. Therefore, it is to be understood that the invention
disclosed herein is intended to cover such modifications as fall within
the scope of the appended claims.

Patent applications by Andrew J. Shooter, Altrincham GB

Patent applications by Stuart N. Richards, Frodsham GB

Patent applications by LUBRIZOL ADVANCED MATERIALS, INC.

Patent applications in class Reactant contains at least one ethylenically unsaturated group

Patent applications in all subclasses Reactant contains at least one ethylenically unsaturated group